"Put one foot in front of the other, and soon you'll be walking out the door...." That's right, putting your feet into motion is what you need to do to walk.
The words walk isn't just used to describe the action of taking one step in front of the other. In baseball, it's a term for when a batter receives four balls and is given the right to walk to first base. When a horse's gate is slow and it keeps two feel always on the ground, that's a walk. When you choose a particular path for yourself in life, you could call that a walk of life.