4.27 Online SubsystemSteam CreateSession failing?

[uced]

For anyone bumping into this problem.
The solution is here:

Unreal 4.27.2 Steam SDK 1.51 Can't Find my own session #4.27.2 #Steam #Sessions

I worked before with C Sharp in unity. I have visual studio installed yes and my project is also a c++ project but i dont have nothing writting in c++ yet.