Just Login and Log off base on Identity 2 or any Claims-based identity

Hi dear ,

I have an WebApplication base on ASP.Net MVC 5 .My database was created in sqlserver( i use database first ) so for authentication i dont need to create new tables because i have my tables.

I want just Set Cookie base on Identity 2 and Log off

var result = objUser.Login(username ,password);//check exist
            if(result.IsValid == true)
            {
// set cookie and login
}

what is best solution .How can i do it?

please help me

thanks