Samid.Domain:

Entities
ValueObjects
Interfaces
Domain Events
Domain Exceptions

Samid.Application:

Interfaces
Services
DTOs
Exceptions
UseCases

Samid.Infrastructure:

Persistence (Repositories, DbContext)
ExternalServices (Integrations, External APIs)
Mappings (Entity Framework Mappings, AutoMapper Profiles)
Configurations (Configuration files and settings)

Samid.Api:

Controllers
Models (API Models, ViewModels)
Middlewares
Configurations (Dependency Injection, API Settings)

dotnet ef migrations add InitialCreate --project Samid.Infrastructure --startup-project Samid.Api --context ApplicationDbContext

dotnet ef database update --project Samid.Infrastructure --startup-project Samid.Api --context ApplicationDbContext