Static friction just holds the foot stationary. That is all.
When you take a step on the ground, the muscles in your leg press your foot backwards and the rest of your body forwards. Since the foot can't go backwards due to static friction, the rest of your body goes much more forwards, because the leg still must stretch as the muscles force it to.
So, basically, static friction makes it possible for you to push yourself away from the ground. But it isn't the force that actually does it. Just like you can push yourself away from a wall. That makes you speed up, not because the wall supplies any energy to you, but because the energy you put into jolting your arms backwards into the wall results in the rest of your body moving the opposite way since the arms ain't moving backwards.
This is Newton's 3rd law.