Remix this project that contains some starter code. Then make your own version of a flappy bird game. Create more obstacles/levels, a win or lose message, a score... Use the space bar to raise the object up and get it around the blue blockers. The object will wait a bit at the start before it starts to fall.
Thank you to @dcallanit for the Flappy Bird inspiration (https://scratch.mit.edu/projects/18150809). See my example here: https://scratch.mit.edu/projects/364579672/