In GDevelop (Game Engine), you cannot edit the hitboxes if it is a tilemap (As far as i know). I fixed most of it. As for the blue bar, that is your energy. If you pay attention, whenever you move it subtracts, and when you collect coins, it adds up to the blue bar and the red bar. Blue Bar: Energy. Red Bar: Health. (I have tested the game across different devices, and it can be won, but it is meant to be hard.)