diff --git a/API_SQLuedo/API/Controllers/InquiriesController.cs b/API_SQLuedo/API/Controllers/InquiriesController.cs
index dc2201d..e29ef16 100644
--- a/API_SQLuedo/API/Controllers/InquiriesController.cs
+++ b/API_SQLuedo/API/Controllers/InquiriesController.cs
@@ -10,26 +10,25 @@ namespace API.Controllers
     [ApiController]
     public class InquiriesController : Controller
     {
-        private IDataService _inquiryDataService;
+        private IDataService<InquiryDTO> _dataService;
 
         private readonly ILogger<UsersController> _logger;
-
-        public InquiriesController(IDataService inquiryDataService)
+        public InquiriesController(IDataService<InquiryDTO> dataService)
         {
-            _inquiryDataService = inquiryDataService;
+            _dataService = _dataService;
         }
 
         [HttpGet("inquiries/{page}/{number}")]
         public IActionResult GetInquiries(int page, int number)
         {
-            var nbInquiry = _inquiryDataService.GetInquiries(page, number).Count();
+            var nbInquiry = _dataService.InquiryDataService.GetInquiries(page, number).Count();
             if (nbInquiry == 0)
             {
                 _logger.LogError("[ERREUR] Aucune enquête trouvée.");
                 return StatusCode(204);
             }
             _logger.LogInformation("[INFORMATION] {nb} Enquête(s) trouvée(s)", nbInquiry);
-            return Ok(_inquiryDataService.GetInquiries(page, number));
+            return Ok(_dataService.InquiryDataService.GetInquiries(page, number));
         }
 
         [HttpGet("inquiry/id/{id}")]
@@ -38,7 +37,7 @@ namespace API.Controllers
             try
             {
                 _logger.LogInformation("[INFORMATION] L'enquête avec l'id {id} a été trouvé.", id);
-                return Ok(_inquiryDataService.GetInquiryById(id));
+                return Ok(_dataService.InquiryDataService.GetInquiryById(id));
             }
             catch (ArgumentException)
             {
@@ -53,7 +52,7 @@ namespace API.Controllers
             try
             {
                 _logger.LogInformation("[INFORMATION] L'enquête avec le titre {title} a été trouvé.", title);
-                return Ok(_inquiryDataService.GetInquiryByTitle(title));
+                return Ok(_dataService.InquiryDataService.GetInquiryByTitle(title));
             }
             catch (ArgumentException)
             {
@@ -65,11 +64,11 @@ namespace API.Controllers
         [HttpDelete]
         public IActionResult DeleteInquiry(int id)
         {
-            var success = _inquiryDataService.DeleteInquiry(id);
+            var success = _dataService.InquiryDataService.DeleteInquiry(id);
             if (success)
             {
                 _logger.LogInformation("[INFORMATION] L'enquête avec l'id {id} a été supprimé.", id);
-                return Ok(_inquiryDataService.DeleteInquiry(id));
+                return Ok(_dataService.InquiryDataService.DeleteInquiry(id));
             }
             else
             {
@@ -87,7 +86,7 @@ namespace API.Controllers
                 return BadRequest();
             }
             _logger.LogInformation("[INFORMATION] Une enquête a été créé : title - {title}, description - {description}, isUser - {isUser}, database - {database}, inquiryTable - {inquiryTable}", dto.Title, dto.Description, dto.IsUser, dto.Database, dto.InquiryTable);
-            return Created(nameof(GetInquiries), _inquiryDataService.CreateInquiry(dto.Title, dto.Description, dto.IsUser, dto.Database, dto.InquiryTable));
+            return Created(nameof(GetInquiries), _dataService.InquiryDataService.CreateInquiry(dto.Title, dto.Description, dto.IsUser, dto.Database, dto.InquiryTable));
         }
 
         [HttpPut]
@@ -106,7 +105,7 @@ namespace API.Controllers
             if (inquiryDTO != null)
             {
                 _logger.LogInformation("[INFORMATION] La mise à jour de l'enquête avec l'id {id} a été effectuée", id);
-                return Ok(_inquiryDataService.UpdateInquiry(id, inquiryDTO));
+                return Ok(_dataService.InquiryDataService.UpdateInquiry(id, inquiryDTO));
             }
             _logger.LogError("[ERREUR] Aucune enquête trouvée avec l'id {id}.", id);
             return NotFound();
diff --git a/API_SQLuedo/API/Controllers/LessonsController.cs b/API_SQLuedo/API/Controllers/LessonsController.cs
index a408f26..02b6a07 100644
--- a/API_SQLuedo/API/Controllers/LessonsController.cs
+++ b/API_SQLuedo/API/Controllers/LessonsController.cs
@@ -10,26 +10,25 @@ namespace API.Controllers
     [ApiController]
     public class LessonsController : Controller
     {
-        private IDataService _lessonDataService;
+        private IDataService<LessonDTO> _dataService;
 
         private readonly ILogger<UsersController> _logger;
-
-        public LessonsController(IDataService lessonDataService)
+        public LessonsController(IDataService<LessonDTO> dataService)
         {
-            _lessonDataService = lessonDataService;
+            _dataService = dataService;
         }
 
         [HttpGet("lessons/{page}/{number}")]
         public IActionResult GetLessons(int page, int number)
         {
-            var nbLesson = _lessonDataService.GetInquiries(page, number).Count();
+            var nbLesson = _dataService.LessonDataService.GetLessons(page, number).Count();
             if (nbLesson == 0)
             {
                 _logger.LogError("[ERREUR] Aucune leçon trouvée.");
                 return StatusCode(204);
             }
             _logger.LogInformation("[INFORMATION] {nb} Leçon(s) trouvée(s)", nbLesson);
-            return Ok(_lessonDataService.GetLessons(page, number));
+            return Ok(_dataService.LessonDataService.GetLessons(page, number));
         }
 
         [HttpGet("lesson/id/{id}")]
@@ -38,7 +37,7 @@ namespace API.Controllers
             try
             {
                 _logger.LogInformation("[INFORMATION] La leçon avec l'id {id} a été trouvé.", id);
-                return Ok(_lessonDataService.GetLessonById(id));
+                return Ok(_dataService.LessonDataService.GetLessonById(id));
             }
             catch (ArgumentException)
             {
@@ -53,7 +52,7 @@ namespace API.Controllers
             try
             {
                 _logger.LogInformation("[INFORMATION] La leçon avec le titre {title} a été trouvé.", title);
-                return Ok(_lessonDataService.GetLessonByTitle(title));
+                return Ok(_dataService.LessonDataService.GetLessonByTitle(title));
             }
             catch (ArgumentException)
             {
@@ -65,11 +64,11 @@ namespace API.Controllers
         [HttpDelete]
         public IActionResult DeleteLesson(int id)
         {
-            var success = _lessonDataService.DeleteLesson(id);
+            var success = _dataService.LessonDataService.DeleteLesson(id);
             if (success)
             {
                 _logger.LogInformation("[INFORMATION] La leçon avec l'id {id} a été supprimé.", id);
-                return Ok(_lessonDataService.DeleteLesson(id));
+                return Ok(_dataService.LessonDataService.DeleteLesson(id));
             }
             else
             {
@@ -87,7 +86,7 @@ namespace API.Controllers
                 return BadRequest();
             }
             _logger.LogInformation("[INFORMATION] Une leçon a été créé : title - {title}, lastPublisher - {publisher}, lastEdit - {lastEdit}", dto.Title, dto.LastPublisher, dto.LastEdit);
-            return Created(nameof(GetLessons), _lessonDataService.CreateLesson(dto.Title, dto.LastPublisher, dto.LastEdit));
+            return Created(nameof(GetLessons), _dataService.LessonDataService.CreateLesson(dto.Title, dto.LastPublisher, dto.LastEdit));
         }
 
         [HttpPut]
@@ -106,7 +105,7 @@ namespace API.Controllers
             if (lessonDTO != null)
             {
                 _logger.LogInformation("[INFORMATION] La mise à jour de la leçon avec l'id {id} a été effectuée", id);
-                return Ok(_lessonDataService.UpdateLesson(id, lessonDTO));
+                return Ok(_dataService.LessonDataService.UpdateLesson(id, lessonDTO));
             }
             _logger.LogError("[ERREUR] Aucune leçon trouvée avec l'id {id}.", id);
             return NotFound();
diff --git a/API_SQLuedo/API/Controllers/UsersController.cs b/API_SQLuedo/API/Controllers/UsersController.cs
index ca36890..6a4b462 100644
--- a/API_SQLuedo/API/Controllers/UsersController.cs
+++ b/API_SQLuedo/API/Controllers/UsersController.cs
@@ -1,9 +1,12 @@
 using DbContextLib;
+using Entities.SQLudeoDB;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
+using Model;
 using Model.Business;
 using Model.DTO;
+using Model.Mappers;
 using Services;
 
 namespace API.Controllers
@@ -13,27 +16,26 @@ namespace API.Controllers
     [ApiController]
     public class UsersController : Controller
     {
-        private IDataService _userDataService;
+        private IDataService<UserDTO?> _dataService;
 
         private readonly ILogger<UsersController> _logger;
-
-        public UsersController(IDataService userDataService, ILogger<UsersController> logger)
+        public UsersController(IDataService<UserDTO?> dataService, ILogger<UsersController> logger)
         {
-            _userDataService = userDataService;
+            _dataService = dataService;
             _logger = logger;
         }
 
         [HttpGet("users/{page}/{number}")]
         public async Task<IActionResult> GetUsers(int page, int number) 
         {
-            var nbUser = (await _userDataService.GetUsers(page, number)).ToList().Count();
+            var nbUser = (await _dataService.UserService.GetUsers(page, number)).ToList().Count();
             if(nbUser == 0) 
             {
                 _logger.LogError("[ERREUR] Aucun utilisateur trouvé.");
                 return StatusCode(204);
             }
             _logger.LogInformation("[INFORMATION] {nb} Utilisateur(s) trouvé(s)", nbUser);
-            return Ok(_userDataService.GetUsers(page, number));
+            return Ok(_dataService.UserService.GetItems<UserEntity>(page, number));
         }
 
         [HttpGet("user/id/{id}")]
@@ -42,7 +44,7 @@ namespace API.Controllers
             try
             {
                 _logger.LogInformation("[INFORMATION] Utilisateur avec l'id {id} a été trouvé.", id);
-                return Ok(_userDataService.GetUserById(id));
+                return Ok(_dataService.UserService.GetItems<UserEntity>(1, 1, UserProperty.Id.ToString(),id));
             } catch (ArgumentException) 
             {
                 _logger.LogError("[ERREUR] Aucun utilisateur trouvé avec l'id {id}.", id);
@@ -56,7 +58,7 @@ namespace API.Controllers
             try
             {
                 _logger.LogInformation("[INFORMATION] Utilisateur avec l'username {username} a été trouvé.", username);
-                return Ok(_userDataService.GetUserByUsername(username));
+                return Ok(_dataService.UserService.GetItems<UserEntity>(1, 1,UserProperty.Username.ToString(), username));
             }catch (ArgumentException) 
             {
                 _logger.LogError("[ERREUR] Aucun utilisateur trouvé avec l'username {username}.", username);
@@ -68,11 +70,11 @@ namespace API.Controllers
         [HttpDelete]
         public async Task<IActionResult> DeleteUser(int id)
         {
-            var success = await _userDataService.DeleteUser(id);
+            var success = await _dataService.UserService.DeleteItem<UserEntity>(id);
             if(success)
             {
                 _logger.LogInformation("[INFORMATION] L'utilisateur avec l'id {id} a été supprimé.", id);
-                return Ok(_userDataService.DeleteUser(id));
+                return Ok(_dataService.UserService.DeleteUser(id));
             } else
             {
                 _logger.LogError("[ERREUR] Aucun utilisateur trouvé avec l'id {id}.", id);
@@ -88,9 +90,9 @@ namespace API.Controllers
             {
                 return BadRequest();
             }
-            // return Ok(_userDataService.CreateUser(username, password, email, isAdmin));
+
             _logger.LogInformation("[INFORMATION] Un utilisateur a été créé : username - {username}, password - {password}, email - {email}, isAdmin - {isAdmin}", dto.Username, dto.Password, dto.Email, dto.IsAdmin);
-            return Created(nameof(GetUsers), _userDataService.CreateUser(dto.Username, dto.Password, dto.Email, dto.IsAdmin));
+            return Created(nameof(GetUsers), _dataService.UserService.AddItem(dto.FromDTOToModel().FromModelToEntity()));
         }
 
         [HttpPut]
@@ -109,7 +111,7 @@ namespace API.Controllers
             if(userDTO != null) 
             {
                 _logger.LogInformation("[INFORMATION] La mise à jour de l'utilisateur avec l'id {id} a été effectuée", id);
-                return Ok(_userDataService.UpdateUser(id, userDTO));
+                return Ok(_dataService.UserService.UpdateItem<UserEntity, UserDTO>(id, userDTO));
             }
             _logger.LogError("[ERREUR] Aucun utilisateur trouvé avec l'id {id}.", id);
             return NotFound(); 
diff --git a/API_SQLuedo/API/Program.cs b/API_SQLuedo/API/Program.cs
index eb3ee3c..c3d1a86 100644
--- a/API_SQLuedo/API/Program.cs
+++ b/API_SQLuedo/API/Program.cs
@@ -3,9 +3,12 @@ using DbContextLib;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.OpenApi.Models;
+using Model.DTO;
+using Model.Business;
 using ModelToEntity;
 using Services;
 using System.Data.Common;
+using Microsoft.Extensions.Options;
 
 var builder = WebApplication.CreateBuilder(args);
 
@@ -15,8 +18,9 @@ builder.Services.AddControllers();
 // Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
 builder.Services.AddEndpointsApiExplorer();
 builder.Services.AddSwaggerGen();
-builder.Services.AddScoped<IDataService, UserDataService>();
-builder.Services.AddScoped<IDataServiceEF, DbDataManager>();
+builder.Services.AddScoped<IUserDataService<UserDTO>, UserDataService>();
+builder.Services.AddScoped<IDataService<UserDTO?>, DataService>();
+builder.Services.AddScoped<IUserDataService<User>, DbDataManager>();
 builder.Services.AddDbContext<DbContext, UserDbContext>();
 builder.Services.AddDbContext<WebAPIDbContext>(options => options.UseInMemoryDatabase("appDb"));
 builder.Services.AddIdentityApiEndpoints<IdentityUser>().AddEntityFrameworkStores<WebAPIDbContext>();
diff --git a/API_SQLuedo/API_SQLuedo.sln b/API_SQLuedo/API_SQLuedo.sln
index f9b50ec..0d2bfac 100644
--- a/API_SQLuedo/API_SQLuedo.sln
+++ b/API_SQLuedo/API_SQLuedo.sln
@@ -17,7 +17,9 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "DbContextLib", "DbContextLi
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Services", "Services\Services.csproj", "{9BD3DCBA-AFD8-47FA-B07C-613B53E63968}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ModelToEntity", "ModelToEntity\ModelToEntity.csproj", "{8F53CC62-94B3-4F9D-ABF1-F7307A6F27C0}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ModelToEntity", "ModelToEntity\ModelToEntity.csproj", "{8F53CC62-94B3-4F9D-ABF1-F7307A6F27C0}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Shared", "Shared\Shared.csproj", "{B28FD539-6FE4-4B13-9C1F-D88F4771CC69}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -57,6 +59,10 @@ Global
 		{8F53CC62-94B3-4F9D-ABF1-F7307A6F27C0}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{8F53CC62-94B3-4F9D-ABF1-F7307A6F27C0}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{8F53CC62-94B3-4F9D-ABF1-F7307A6F27C0}.Release|Any CPU.Build.0 = Release|Any CPU
+		{B28FD539-6FE4-4B13-9C1F-D88F4771CC69}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{B28FD539-6FE4-4B13-9C1F-D88F4771CC69}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{B28FD539-6FE4-4B13-9C1F-D88F4771CC69}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{B28FD539-6FE4-4B13-9C1F-D88F4771CC69}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
diff --git a/API_SQLuedo/DbContextLib/UserDbContext.cs b/API_SQLuedo/DbContextLib/UserDbContext.cs
index 4bf3c4e..a5acbf6 100644
--- a/API_SQLuedo/DbContextLib/UserDbContext.cs
+++ b/API_SQLuedo/DbContextLib/UserDbContext.cs
@@ -25,7 +25,7 @@ namespace DbContextLib
         {
             if (!optionsBuilder.IsConfigured)
             {
-                optionsBuilder.UseNpgsql("Host=localhost;Database=SQLuedo;Username=admin;Password=motdepasse");
+                optionsBuilder.UseNpgsql("Host=localhost;Database=SQLuedo;Username=admin;Password=motdepasse").EnableSensitiveDataLogging();
             }
             base.OnConfiguring(optionsBuilder);
         }
diff --git a/API_SQLuedo/Model/UserProperty.cs b/API_SQLuedo/Model/UserProperty.cs
new file mode 100644
index 0000000..75ecf9c
--- /dev/null
+++ b/API_SQLuedo/Model/UserProperty.cs
@@ -0,0 +1,18 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Model
+{
+    public enum UserProperty
+    {
+        Id,
+        Username,
+        Password,
+        Email,
+        IsAdmin
+
+    }
+}
diff --git a/API_SQLuedo/ModelToEntity/DbDataManager.cs b/API_SQLuedo/ModelToEntity/DbDataManager.cs
index 7ae486b..c56dcf4 100644
--- a/API_SQLuedo/ModelToEntity/DbDataManager.cs
+++ b/API_SQLuedo/ModelToEntity/DbDataManager.cs
@@ -6,10 +6,13 @@ using DbContextLib;
 using Model.Business;
 using Model;
 using Model.Mappers;
+using System;
+using Microsoft.AspNetCore.Identity;
+using System.Runtime.InteropServices.ObjectiveC;
 
 namespace ModelToEntity
 {
-    public class DbDataManager : IDataServiceEF
+    public class DbDataManager : IUserDataService<User?>
     {
         public async Task<User> GetUserById(int id)
         {
@@ -93,7 +96,7 @@ namespace ModelToEntity
                     IsAdmin = isAdmin
                 };
                 context.Users.Add(newUserEntity.FromDTOToModel().FromModelToEntity());
-                context.SaveChangesAsync();
+                context.SaveChanges();
 
                 return  await Task.FromResult(newUserEntity.FromDTOToModel());
             }
@@ -157,6 +160,39 @@ namespace ModelToEntity
         {
             throw new NotImplementedException();
         }
-    }
-   
+
+        public async Task<T?> AddItem<T>(T? item) where T : class
+        {
+            using (var context = new UserDbContext())
+            {
+                return await context.CreateItemAsync(item);
+            }
+
+        }
+
+        public async Task<bool> DeleteItem<T>(int id) where T : class
+        {
+           using(var context = new UserDbContext())
+            {
+                return await context.DeleteItemAsync<T>(id);
+            }
+        }
+        public async Task<T?> UpdateItem<T, TDto>(int? id, TDto? newItem)
+            where T : class
+            where TDto : class
+        {
+            using(var context = new UserDbContext()) 
+            {
+                return await context.UpdateItemAsync<T, TDto>(id, newItem);
+            }  
+        }
+
+        public async Task<IEnumerable<T?>> GetItems<T>(int index, int count, string? orderingPropertyName = null, object? valueProperty = null) where T : class
+        {
+            using (var context = new UserDbContext())
+            {
+                return await context.GetItemsWithFilter<T>(index, count, orderingPropertyName, valueProperty);
+            }
+        }
+    }  
 }
diff --git a/API_SQLuedo/ModelToEntity/Extension.cs b/API_SQLuedo/ModelToEntity/Extension.cs
index b039fe4..508e872 100644
--- a/API_SQLuedo/ModelToEntity/Extension.cs
+++ b/API_SQLuedo/ModelToEntity/Extension.cs
@@ -7,10 +7,98 @@ using System.Threading.Tasks;
 using Entities;
 using Entities.SQLudeoDB;
 using Model.Business;
+using System.Diagnostics;
+using DbContextLib;
+using Microsoft.EntityFrameworkCore;
+using System.Linq.Expressions;
+using Microsoft.EntityFrameworkCore.Metadata.Internal;
 
 namespace ModelToEntity
 {
-    static class Extension
+    internal static class Extension
     {
+        internal static Task<T?> CreateItemAsync<T>(this DbContext context, T? item) where T : class
+        {
+            if (item == null || context.Set<T>().Contains(item))
+            {
+                return Task.FromResult<T?>(default(T));
+            }
+
+            context.Set<T>().Add(item);
+            context.SaveChangesAsync();
+
+            return Task.FromResult<T?>(item);
+        }
+        internal static async Task<bool> DeleteItemAsync<T>(this DbContext context, int? id) where T : class
+        {
+            if (id == null)
+            {
+                return false;
+            }
+
+            var entity = await context.Set<T>().FindAsync(id);
+            if (entity == null)
+            {
+                return false;
+            }
+
+            context.Set<T>().Remove(entity);
+            await context.SaveChangesAsync();
+
+            return true;
+        }
+        internal static Task<T?> UpdateItemAsync<T, TDto>(this DbContext context, int? id, TDto dto)
+        where T : class
+        where TDto : class
+        {
+            var entity = context.Set<T>().Find(id);
+            if (entity == null)
+            {
+                throw new ArgumentException("Impossible de trouver l'entité", nameof(id));
+            }
+
+            var propertiesToUpdate = typeof(TDto).GetProperties()
+                                                  .Where(p => p.CanRead && p.CanWrite);
+
+            foreach (var property in propertiesToUpdate)
+            {
+                var value = property.GetValue(dto);
+                typeof(T).GetProperty(property.Name)?.SetValue(entity, value);
+            }
+
+            context.Entry(entity).State = EntityState.Modified;
+            context.SaveChanges();
+
+            return Task.FromResult<T?>(entity);
+        }
+        internal static Task<IEnumerable<T?>> GetItemsWithFilter<T>(this DbContext context,
+            int index, int count, string? orderingPropertyName = null, object valueProperty = null) where T : class
+        {
+            IQueryable<T> query = context.Set<T>();
+
+            if (valueProperty != null && !string.IsNullOrEmpty(orderingPropertyName))
+            {
+                var prop = typeof(T).GetProperty(orderingPropertyName);
+                if (prop != null)
+                {
+                    var idProp = typeof(T).GetProperty(orderingPropertyName);
+                    if (idProp != null)
+                    {
+                        var parameter = Expression.Parameter(typeof(T), "entity");
+                        var propertyAccess = Expression.Property(parameter, prop);
+                        var constant = Expression.Constant(valueProperty);
+                        var equality = Expression.Equal(propertyAccess, constant);
+                        var lambda = Expression.Lambda<Func<T, bool>>(equality, parameter);
+                        var filteredEntity = context.Set<T>().FirstOrDefault(lambda);
+                        if (filteredEntity != null)
+                        {
+                            return Task.FromResult<IEnumerable<T?>>(new List<T?> { filteredEntity });
+                        }
+                    }
+                }
+            }
+            var items = query.Skip(index).Take(count).ToList();
+            return Task.FromResult<IEnumerable<T?>>(items);
+        }
     }
-}
+}
\ No newline at end of file
diff --git a/API_SQLuedo/ModelToEntity/ModelToEntity.csproj b/API_SQLuedo/ModelToEntity/ModelToEntity.csproj
index 4cd7b1b..472379f 100644
--- a/API_SQLuedo/ModelToEntity/ModelToEntity.csproj
+++ b/API_SQLuedo/ModelToEntity/ModelToEntity.csproj
@@ -23,6 +23,7 @@
     <ProjectReference Include="..\DbContextLib\DbContextLib.csproj" />
     <ProjectReference Include="..\EntityFramework\Entities.csproj" />
     <ProjectReference Include="..\Model\Model.csproj" />
+    <ProjectReference Include="..\Shared\Shared.csproj" />
   </ItemGroup>
 
 </Project>
diff --git a/API_SQLuedo/Services/DataService.cs b/API_SQLuedo/Services/DataService.cs
new file mode 100644
index 0000000..cb0e072
--- /dev/null
+++ b/API_SQLuedo/Services/DataService.cs
@@ -0,0 +1,24 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Model.Business;
+using Model.DTO;
+using Shared;
+
+namespace Services
+{
+    public class DataService : IDataService<UserDTO>
+    {
+        public IUserDataService<UserDTO?> UserService { get; }
+        public DataService(IUserDataService<UserDTO?> userDataService) 
+        {
+            UserService = userDataService;
+        }
+
+        public IInquiryDataService InquiryDataService { get; }
+
+        public ILessonDataService LessonDataService { get; }
+    }
+}
diff --git a/API_SQLuedo/Services/LessonDataService.cs b/API_SQLuedo/Services/LessonDataService.cs
new file mode 100644
index 0000000..a21a5a7
--- /dev/null
+++ b/API_SQLuedo/Services/LessonDataService.cs
@@ -0,0 +1,12 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Services
+{
+    public class LessonDataService
+    {
+    }
+}
diff --git a/API_SQLuedo/Services/Services.csproj b/API_SQLuedo/Services/Services.csproj
index dd690cb..4f252a2 100644
--- a/API_SQLuedo/Services/Services.csproj
+++ b/API_SQLuedo/Services/Services.csproj
@@ -24,6 +24,7 @@
     <ProjectReference Include="..\EntityFramework\Entities.csproj" />
    <ProjectReference Include="..\ModelToEntity\ModelToEntity.csproj" />
     <ProjectReference Include="..\Model\Model.csproj" />
+    <ProjectReference Include="..\Shared\Shared.csproj" />
   </ItemGroup>
 
 </Project>
diff --git a/API_SQLuedo/Services/UserDataService.cs b/API_SQLuedo/Services/UserDataService.cs
index 995010a..82d6c0d 100644
--- a/API_SQLuedo/Services/UserDataService.cs
+++ b/API_SQLuedo/Services/UserDataService.cs
@@ -1,119 +1,83 @@
-using DbContextLib;
-using Model.DTO;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-using Model.Mappers;
-using Model.Business;
-using Microsoft.EntityFrameworkCore;
-using Entities.SQLudeoDB;
-using ModelToEntity;
-
-namespace Services
-{
-    public class UserDataService : IDataService
-    {
-        private UserDbContext DbContext { get; set; }
-        private readonly IDataServiceEF dataServiceEF;
-        public UserDataService(IDataServiceEF dataServiceEF) 
-        {
-            this.dataServiceEF = dataServiceEF;
-        }
-
-        public async Task<UserDTO> GetUserById(int id)
+using DbContextLib;
+using Model.DTO;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Model.Mappers;
+using Model.Business;
+using Microsoft.EntityFrameworkCore;
+using Entities.SQLudeoDB;
+using ModelToEntity;
+
+namespace Services
+{
+    public class UserDataService : IUserDataService<UserDTO?>
+    {
+        private readonly IUserDataService<User> dataServiceEF;
+        public UserDataService(IUserDataService<User> dataServiceEF) 
+        {
+            this.dataServiceEF = dataServiceEF;
+        }
+
+        public async Task<UserDTO?> GetUserById(int id)
         {
             var user = await dataServiceEF.GetUserById(id);
-            return user.FromModelToDTO();
-        }
-
-        public async Task<UserDTO> GetUserByUsername(string username)
-        {
-            var user = await dataServiceEF.GetUserByUsername(username);
-            return user.FromModelToDTO();
-        }
-
-        public async Task<IEnumerable<UserDTO>> GetUsers(int page, int number)
-        {
-            var users =  await dataServiceEF.GetUsers(page, number);
-            return users.Select(u => u.FromModelToDTO());
-        }
-
-        public async Task<bool> DeleteUser(int id)
-        {
-            var respons = await dataServiceEF.DeleteUser(id);
-            return respons;
-        }
-
-        public async Task<UserDTO> UpdateUser(int id, UserDTO user)
-        {
-            var updatingUser = await dataServiceEF.UpdateUser(id, user);
+            return user.FromModelToDTO();
+        }
+
+        public async Task<UserDTO?> GetUserByUsername(string username)
+        {
+            var user = await dataServiceEF.GetUserByUsername(username);
+            return user.FromModelToDTO();
+        }
+
+        public async Task<IEnumerable<UserDTO?>> GetUsers(int page, int number)
+        {
+            var users =  await dataServiceEF.GetUsers(page, number);
+            return users.Select(u => u.FromModelToDTO());
+        }
+
+        public async Task<bool> DeleteUser(int id)
+        {
+            var respons = await dataServiceEF.DeleteUser(id);
+            return respons;
+        }
+
+        public async Task<UserDTO?> UpdateUser(int id, UserDTO user)
+        {
+            var updatingUser = await dataServiceEF.UpdateUser(id, user);
             return updatingUser.FromModelToDTO();
-        }
-        public async Task<UserDTO> CreateUser(string username, string password, string email, bool isAdmin)
-        {
-            var newUserEntity =  await dataServiceEF.CreateUser(username, password, email, isAdmin);
-            return newUserEntity.FromModelToDTO();
-        }
-
-        public IEnumerable<InquiryDTO> GetInquiries(int page, int number)
-        {
-            throw new NotImplementedException();
+        }
+        public async Task<UserDTO?> CreateUser(string username, string password, string email, bool isAdmin)
+        {
+            var newUserEntity =  await dataServiceEF.CreateUser(username, password, email, isAdmin);
+            return newUserEntity.FromModelToDTO();
         }
 
-        public InquiryDTO GetInquiryById(int id)
+        public async Task<T?> AddItem<T>(T? item) where T : class
         {
-            throw new NotImplementedException();
+            var newItem = dataServiceEF.AddItem(item);
+            return await newItem;
         }
 
-        public InquiryDTO GetInquiryByTitle(string title)
+        public Task<bool> DeleteItem<T>(int id) where T : class
         {
-            throw new NotImplementedException();
-        }
-        public UserDTO CreateInquiry(string title, string description, bool isUser, InquiryTableEntity database, SolutionEntity inquiryTable)
-        {
-            throw new NotImplementedException();
+            var succes = dataServiceEF.DeleteItem<T>(id);
+            return succes;
         }
 
-        public bool DeleteInquiry(int id)
+        public Task<T> UpdateItem<T, TDto>(int? id, TDto? newItem) where T : class where TDto : class
         {
-            throw new NotImplementedException();
+            var item = dataServiceEF.UpdateItem<T, TDto>(id, newItem);
+            return item;
         }
 
-        public InquiryDTO UpdateInquiry(int id, InquiryDTO inquiry)
+        public Task<IEnumerable<T?>> GetItems<T>(int index, int count, string? orderingPropertyName = null, object? valueProperty = null) where T : class
         {
-            throw new NotImplementedException();
-        }
-
-        public IEnumerable<InquiryDTO> GetLessons(int page, int number)
-        {
-            throw new NotImplementedException();
-        }
-
-        public InquiryDTO GetLessonById(int id)
-        {
-            throw new NotImplementedException();
-        }
-
-        public InquiryDTO GetLessonByTitle(string title)
-        {
-            throw new NotImplementedException();
-        }
-
-        public bool DeleteLesson(int id)
-        {
-            throw new NotImplementedException();
-        }
-
-        public InquiryDTO UpdateLesson(int id, LessonDTO lesson)
-        {
-            throw new NotImplementedException();
-        }
-
-        public UserDTO CreateLesson(string title, string lastPublisher, DateOnly lastEdit)
-        {
-            throw new NotImplementedException();
+           var items = dataServiceEF.GetItems<T>(index, count, orderingPropertyName, valueProperty);
+            return items;
         }
 
         public Task<IEnumerable<ParagraphDTO>> GetParagraphs(int page, int number)
diff --git a/API_SQLuedo/Shared/IDataService.cs b/API_SQLuedo/Shared/IDataService.cs
new file mode 100644
index 0000000..7c3b82b
--- /dev/null
+++ b/API_SQLuedo/Shared/IDataService.cs
@@ -0,0 +1,13 @@
+using Entities.SQLudeoDB;
+using Model.Business;
+using Model.DTO;
+
+namespace Services
+{
+    public interface IDataService<T> where T : class
+    {
+        IUserDataService<T?> UserService { get; }
+        IInquiryDataService InquiryDataService { get; }
+        ILessonDataService LessonDataService { get; }
+    }
+}
diff --git a/API_SQLuedo/Shared/IGenericService.cs b/API_SQLuedo/Shared/IGenericService.cs
new file mode 100644
index 0000000..4e84eaf
--- /dev/null
+++ b/API_SQLuedo/Shared/IGenericService.cs
@@ -0,0 +1,10 @@
+namespace Shared
+{
+    public interface IGenericService<T> where T : class
+    {
+        public Task<T?> AddItem<T>(T? item) where T : class;
+        public Task<bool> DeleteItem<T>(int id) where T : class;
+        public Task<T> UpdateItem<T, TDto>(int? id, TDto? newItem) where T : class where TDto : class;
+        public Task<IEnumerable<T>> GetItems<T>(int index, int count, string? orderingPropertyName = null, object? valueProperty = null) where T : class;
+    }
+}
diff --git a/API_SQLuedo/Shared/IInquiryDataService.cs b/API_SQLuedo/Shared/IInquiryDataService.cs
new file mode 100644
index 0000000..0e71be5
--- /dev/null
+++ b/API_SQLuedo/Shared/IInquiryDataService.cs
@@ -0,0 +1,21 @@
+using Entities.SQLudeoDB;
+using Model.DTO;
+using Shared;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Services
+{
+    public interface IInquiryDataService : IGenericService<InquiryDTO>
+    {
+        public IEnumerable<InquiryDTO> GetInquiries(int page, int number);
+        public InquiryDTO GetInquiryById(int id);
+        public InquiryDTO GetInquiryByTitle(string title);
+        public bool DeleteInquiry(int id);
+        public InquiryDTO UpdateInquiry(int id, InquiryDTO inquiry);
+        public UserDTO CreateInquiry(string title, string description, bool isUser, InquiryTableEntity database, SolutionEntity inquiryTable);
+    }
+}
diff --git a/API_SQLuedo/Shared/ILessonDataService.cs b/API_SQLuedo/Shared/ILessonDataService.cs
new file mode 100644
index 0000000..7321547
--- /dev/null
+++ b/API_SQLuedo/Shared/ILessonDataService.cs
@@ -0,0 +1,20 @@
+using Model.DTO;
+using Shared;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Services
+{
+    public interface ILessonDataService : IGenericService<LessonDTO>
+    {
+        public IEnumerable<InquiryDTO> GetLessons(int page, int number);
+        public InquiryDTO GetLessonById(int id);
+        public InquiryDTO GetLessonByTitle(string title);
+        public bool DeleteLesson(int id);
+        public InquiryDTO UpdateLesson(int id, LessonDTO lesson);
+        public UserDTO CreateLesson(string title, string lastPublisher, DateOnly lastEdit);
+    }
+}
diff --git a/API_SQLuedo/Shared/IUserDataService.cs b/API_SQLuedo/Shared/IUserDataService.cs
new file mode 100644
index 0000000..bf2f2e2
--- /dev/null
+++ b/API_SQLuedo/Shared/IUserDataService.cs
@@ -0,0 +1,23 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Services;
+using Model.DTO;
+using Shared;
+using Model.Business;
+
+namespace Services
+{
+    public interface IUserDataService<T> : IGenericService<T?> where T : class
+    {
+        public Task<IEnumerable<T?>> GetUsers(int page, int number);
+        public Task<T?> GetUserById(int id);
+        public Task<T?> GetUserByUsername(string username);
+        public Task<bool> DeleteUser(int id);
+        public Task<T?> UpdateUser(int id, UserDTO user);
+        public Task<T?> CreateUser(string username, string password, string email, bool isAdmin);
+
+    }
+}
diff --git a/API_SQLuedo/Shared/Shared.csproj b/API_SQLuedo/Shared/Shared.csproj
new file mode 100644
index 0000000..b3751de
--- /dev/null
+++ b/API_SQLuedo/Shared/Shared.csproj
@@ -0,0 +1,13 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\Model\Model.csproj" />
+  </ItemGroup>
+
+</Project>