Midterm Game Idea

When it comes down to my midterm game idea, I want to be able to make a game similar to Flappy Bird or Geometry Dash where you press one button and the character or icon moves up a certain distance, along with obstacles in the way. The objective would be to just go on as long as you can so I could either add a timer or a score, but I think a timer with seconds would be easier. The instructions would be pretty clear too since it is just one button you have to press to play, other than the restart key.