Can exercise, (lunges, squats, etc.) help tighten and tone skin following lipo and a thigh lift?

Lunges and squats will tone the muscles, but you will not be able to exercise the saggy skin away. I would have to see photos or verify with an exam whether a revision is necessary to remove the sagging skin.  Return to your PS for a reevaluation of the outcome of your surgery three years ago. He/she can review with you the pre and post photos showing the results of the thigh/hips/calves lipo and thigh and butt lift and discuss the best options going forward to achieve your end goals.

Thanks for your question, melentc13.
It depends on the amount of loose skin involved. If there’s only a mild degree of sagginess, then maybe exercise will help tighten those areas, although it will take a long time to do that.
Your best option is to consult a reputable and board-certified plastic surgeon and get yourself physically examined. You might need a thigh lift if you have severe sagging in your butt and lower thighs.
Best of luck!

See your doctor again to check into surgical options for excess skin. You can not diet and exercise it away.