Hi Nicole McCormack. Great question! Here are some exercises that you may want to try:
1. Straight Leg Raises.
2.Hamstring Curls.
3. Prone Straight Leg Raises.
4. Wall Squats.
5. Calf Raises.
6. Step-Ups.
7. Side Leg Raises.
8. Leg Presses.
A lot of fitness videos incorporate some version of squats into them. You can always choose to substitute one of the above exercises in place of the squats. The videos that I've attached have limited squats in them (the one by Rocky does not have any squats) so they may be a good place to start.
And if you have hip pain, you may find this video to offer some relief: https://grokker.com/yoga/video/14-day-yoga-challenge-yin-yoga-for-your-hips-i/55aae3b95c8e2d4f23a62038