Here's everything you need to write code for the Session object in ASP.NET Core -- including why you can't expect to migrate your existing ASP.NET MVC application to ASP.NET MVC Core (though Peter has ...

Select “Web Application (Model-View-Controller)” as the project template to create a new ASP.NET Core MVC application.

After installing SignalR, add the necessary ASP.NET MVC routing rules for the Hub API. Open up the App_Start\RouteConfig.cs file and add a using statement for the Microsoft.AspNet.SignalR namespace.