ASP.NET platform was originally developed to serve request and physical pages. This approach worked for year and still works until today in the context of Web Forms. It was a useful pattern when sites were created for individual file-based pages linked together. We still have such pages but the problem is we have to create pages by aggregating data from different endpoints to both the client and the server.
As a solution, a new requirement was made, a HTTP-based endpoints which are capable of serving plain data serialized to JSON strings. This will require more control over the format of the URL.
This article will show you how to route the ASP.NET way: https://www.simple-talk.com/dotnet/asp.net/routing-the-asp.net-way/