Arrow keys or A, W and D to move, R to restart level (do NOT press the green flag or it will set you to level 1!) (all levels are possible) (I checked myself)
Thanks for the ideas @Soccer_Bros I also originated this from the game "the longest platformer ever" (a much better game than this) (It's one of my favorites!) IF YOU GET THE JUMPING GLITCH JUST PRESS "R" GOOD LUCK! (I'd really like to see a remix of this so see what you can do!) :-)