To walk, press A or D. To jump, press W (the longer you hold it, the more higher you jump.
Credits to Sammy Cheez (Youtuber) and others for making platform coding work. Notes: When starting it might not let you jump so restart. But if that didn't happen to you, that's good. Unfortunately, Certain sprites cant be used as it will go through the ground, move everywhere, or unable to move. (BTW this is the most coded game I have ever made)