Left and right arrow keys for scrolling and moving. Up to jump. Use the gear button for music adjustments. Double click flag, just in case it glitches.
Thanks to @Scratched_SC (a.k.a. @-AquaBlaze-), and @smilealot2003. I used the scrolling from @Scratched_SC (a.k.a. @-AquaBlaze-)'s project, and then used @smilealot2003's art for the trees.