database first entity framework core and code first code example
Example: ef core dbfirst
PM> Scaffold-DbContext "Server=.\SQLExpress;Database=SchoolDB;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models
PM> Scaffold-DbContext "Server=.\SQLExpress;Database=SchoolDB;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models