Arrow keys or WASD to move. Wall jumping is impossible. Red kills you. Orange is a trampoline. Purple will explain itself... hehehehehe Blue rectangles move. Ignore the white rectangle on level 5. That is a big mistake and you will enter the realm of more weird glitches. R to repeat level. Every level is 100% possible.
Thanks to @griffpatch for the gravity, the Touch Ground mechanics, and the walking. Help from @queenhater99. Check out the... interesting stuff that he makes on Scratch!