To move left, press the left arrow key; to move right, press the right arrow key. To jump, press the space key. Please follow me and play my games. Tell me in the comments if you like them.
I made this game with these videos: How to Make a Platformer in Scratch, How to Make a Platformer with Ground Detection in Scratch Part 2, and How to Make a Wall-jumping Platformer with Lava Part 3.