The forum

I found the code needed to put in my steam file to let me download a game, but now I am not sure how to run it. I tried the simple possibility and run it through PC Steam, didn't work. I tried to install it into PlayOnMac, but since I do not know where to find the exe file for the game, that didn't work either. How do I get steam games to run? I got a game that I downloaded from GOG to work, but that is the only knowledge on PlayOnMac that I have. Anyone able to help?