ASP.Net Core - relationship between Server, Host and ASP.Net Core app

In context of ASP.Net Core, I want to understand relationship between Server, Host and ASP.Net Core app. Whether Host contains server or vice-versa. How Request and Response flows between Host, server and asp.net core app.

I had tried to Google it and read ASP.Net Core docs, but doesn't get any satisfactory answerer. I want to understand the Architecture and flow in ASP.Net Core.