> I wanted to try to a server backend with it, but I was lost as to which framework to use (ASP.net / .NET Core / .Net 5) so I ended up choosing neither.

The new C# tutorials have solved a lot of this issue just by completely skipping over the legacy parts of .NET (.NET Framework & ASP.NET) and using the CLI to create a new project.

You install .NET 5 (for context, it's just a newer version of .NET Core with the naming realigned), and then write `dotnet new webapi` which will create a new ASP.NET Core API project.