UnrealBuildTool? I have no clue!

Hi, i keep on getting this all the time. but i cannot recall having this before. anyone an idea to fix this?

Missing UE4Game binary.
You may have to build the UE4 project with your IDE. Alternatively, build using UnrealBuildTool with the commandline:
UE4Game <Platform> <Configuration>

I have been searching the forum, and i see this “error” a few more times. But i dont get the solution. I work in 4.16, is it any different?
this should be the answer: I had the same problem after loading the engine from github. Solve it very easy. Adding code to your a pure blueprint project (File->Add Code to Project->None). It allows to be packaged from the menu.

But i have no clue where actually write down this line. Can this be done as a executecommandline inside my Blueprint?