Looking for logging into the _viewstart Page site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the _viewstart Page site. After that you can login as usual with your login credentials.
https://stackoverflow.com/questions/28218866/mvc-login-page-with-custom-layout-and-viewstart
https://www.c-sharpcorner.com/blogs/layouts-and-viewstartcshtml-in-mvc
https://www.tutorialspoint.com/asp.net_core/asp.net_core_razor_view_start.htm
https://github.com/aspnet/Mvc/issues/825
https://www.youtube.com/watch?v=MxU_ugIxnTA
https://www.tutorialsteacher.com/mvc/layout-view-in-asp.net-mvc
https://docs.microsoft.com/de-de/aspnet/core/mvc/views/layout
http://www.dotnet-stuff.com/tutorials/aspnet-mvc/how-to-render-different-layout-in-asp-net-mvc
https://www.learnrazorpages.com/razor-pages/files/viewstart
https://weblogs.asp.net/scottgu/asp-net-mvc-3-layouts
https://exceptionnotfound.net/asp-net-mvc-demystified-layout-viewstart-renderbody-and-rendersection/
https://books.google.de/books?id=ZnHGAER4j-oC&pg=PA271&lpg=PA271&dq=_viewstart+login+page
https://www.codeproject.com/Articles/996879/Various-ways-of-using-Shared-Layout-in-ASP-NET-MVC