Use arrow keys to move Mario. Use the SPACE key to make Mario jump. (If the page asks to use your camera, click the button "Block" because I put the Video Sensing Scratch extension by mistake). Just saying, the timer is kind of glitchy. If you find a glitch, please let me know in the comments.
I got the idea of making this game from a Scratch Tutorial. This is the link to the Scratch Tutorial: https://www.youtube.com/watch?v=eekrc3Xs9Z0&t=4s Make your own game like this game with the link above or you can remix this project. (Don't forget to like this project if you liked it!) New update!! The volume changing feature in this project is added, Settings are added, and changing characters is now available!! (You can now play as Luigi soon!! I will have to work on Luigi's sprites). Thanks to @pensivepanda for the jump code in his/hers project, "mario world 1-1 prototype (wip)"!!!