You use the Mouse, W, Space or up arrow to jump. If you have stayed in the game for 100 seconds, it turns into mini mode, where you fall faster.
This is from Geometry Dash if you liked this (somehow) you should totally play Geometry Dash v1.0.1 - I made it mobile friendly. v1.1 - I added mini mode and made it if you jump it sends out fire, also fixed a bug where if you die you can still jump. v1.1.1 - I added the "High score" variable. v1.2 - I made it so that the farther you go the faster the blocks move and the background changes colour. v1.2.0.1 - I changed the colour of some of the backgrounds and I fixed a bug where the high score is by default 31. v1.2.0.2 - I moved the “High Score” Variable to be on the same x-axis as the “Time” variable and changed the backgrounds to be more softer colours. v1.2.0.3 - I fixed a bug where you can die from the fire touching the blocks. v1.2.1 - I made it so that if you go to far up or down it kills you.