Which exercise helps prepare the knee and kneecap for hiking?

So i have knee problems myself. what my physical theripast told me to you was to sit on the bed with your knees hanging off the side and tighted the kneecap. then you have to lift the leg up and hold for 10 seconds. do sets in 10 and do about 3 sets a day. Or you can do something like leaning against the wall and squating. do about 50 of these each day.

SINGLE LEG SQUAT