its a pretty well known and comlicated program.... so idk... maybe some rule where you can only use the drag and drop tools? or do you have a better suggestion for an engine?

You can definitely use gamemaker. The goal of this game jam is to show developers how little is needed to make a good game. If you're using gamemaker then I'd suggest trying to make art/audio as simply as possible. Really though, I won't force you to use some tool you're not confortable with.