using repository from console project .net core data seeder code example

Example: seeding in ef6

public class SchoolContext: DbContext 
{
    public SchoolContext(): base("SchoolDB") 
    {
        Database.SetInitializer(new SchoolDBInitializer());
    }
    
    public DbSet<Student> Students { get; set; }
    public DbSet<Standard> Standards { get; set; }
}


public class SchoolDBInitializer : DropCreateDatabaseAlways<SchoolDBContext>
{
    protected override void Seed(SchoolDBContext context)
    {
        IList<Standard> defaultStandards = new List<Standard>();

        defaultStandards.Add(new Standard() { StandardName = "Standard 1", Description = "First Standard" });
        defaultStandards.Add(new Standard() { StandardName = "Standard 2", Description = "Second Standard" });
        defaultStandards.Add(new Standard() { StandardName = "Standard 3", Description = "Third Standard" });

        context.Standards.AddRange(defaultStandards);

        base.Seed(context);
    }
}