How to debug code?

Hello. In my VS express I have several Solution Configurations:
Debug Game
DebugGame Editor
Development Editor
I assume that for debugging I need to choose one of the 2 first options (btw, whats the difference?) and launch editor from VS. The problem is I can’t debug engine code - program flow simply not enters function call. With my code everything fine. Do I need to run editor from full source (from github). I thought all should work because I can investigate any API function in VS, so I have access to sources somehow, right?

I use Debug Editor for debug, because with Development Editor debug stops the code but not showing all the values