Idea award Silver Badge Gamer resolution building a game

Hi guys, I don't know how to build the game in the last part of it
"You have completed the manifesto! You need to complete your game to test it works. If you can't manage, perhaps you need to tweak the positions. Just because something works technically, it doesn't mean the level design is fine tuned."
This pops out everytime and I couldn't do anything even I changed the interval. Can anyone tell me how to build the game
Also, I found out that even I tried to press the buttons which is programmed to be moving the character forward, it did nth.
Please help if you could solve the problem, thanks so much!!!