Forward lunges work to strengthen the quadriceps muscle in the front of the thigh that is important for walking.
Stand straight with your arms to the side or on your hips, have a chair close by for support if required.
Take a step forwards on one leg and then drop your hips directly down between both feet, bending both knees
Push back up to the starting position and repeat on the other leg.
Keep your body upright and straight throughout the movement.