Compile and Run Code Online like in leetcode, codewars (ASP.NET CORE or Flask)

I want to write web-platform where users can run the code. (like in leetcode/codewars and another) I can't find any practical information about that. Could someone give me the right direction? (library, article, video) Should I use ASP.NET Core(C#) or Flask(Python) Witch one be more easy to implement?

P.S. I should run sandbox on the server, compile and run code inside in a sandbox?