Walk around the number of times, then knock on the door. Then on to next number. If you walk the wrong way or wrong number, knocking on the door resets the puzzle.
Lmao I forgot about this game after giving up on the first puzzle but I just came back to it and finished it in one go. Honestly, the one I had the most trouble on was the first one, since the key is at the top of the page I thought the directions were going from bottom to top. Bit of a confusing first puzzle but overall pretty good game. Nice job.