How do i make my 2d character move one step at a time?

I’m trying to make a game where the sprites left leg moves, then his right leg in that order by pressing buttons to make him move. Along with the sprite jumping when both the left and right leg button are pressed, and if the wrong button is pressed then the game is over. I’m having a little trouble with the code and I’m stumped on where to even start.

Make another sprite and make him face left side, and make another one and make him face the right side, then you can go animate the sprite in the animate tab. On how to use it search up on google or youtube.