When I run or do form drills, my feet pound the ground and make a loud noise.
This could be a 'form' issue and not an issue of tightness.
Regarding my quads, I am not able to sit on my legs and I can't go all the way down in a squat position. Recommend any exercises?
Most people who are unable to sit down in to a full squat have tightness in the hip or ankle joint. The knee joint is rarely the limiting factor. Whatever the case hurdle mobility drills with large movement amplitudes may help identify and possibly address the problem.