Choose a song in the top right and use the Left [◀ ]and Right [ ▶] arrow keys to move - a mobile friendly version will be coming out soon. The time you have survived is in seconds in the top left above the level you are currently in which progressively gets harder - good luck with getting past 31 seconds!!
The two songs are by bubblebee3 [https://scratch.mit.edu/users/bubblebee3] The music they make is fantastic!