Business Layer Refrence to DAL,MAL Packages Null Create a null IAccount and inherit it on Implementation Data Layer Refrence to MAL Packages Microsoft.EntityFrameworkCore,SqlServer,Tools Create a null IAccount and inherit it on Implementation using Microsoft.AspNetCore.Identity.EntityFrameworkCore; using Microsoft.EntityFrameworkCore; using ModelLayer; Class AppDataContext:- namespace DataLayer { public class AppDataContext: IdentityDbContext<UserModel> { public AppDataContext(DbContextOptions<AppDataContext> options) : base(options) { } } } Model Layer Refrence to Null Packages Microsoft.EntityFrameworkCore.Identity.EntityFrameworkCore,Microsoft.EntityFrameworkCore Class:- UserModel using Microsoft.AspNetCore.Identity; using System.ComponentModel.DataAnnotations; using System.ComponentModel.DataAnnotations.Schema; namespace ModelLayer { public class UserModel: IdentityUser ...