23m-rupture discs w/ 5mm retrolisthesis (l4/5&l5/s1) s/p discectomy surgeon doesn't want surgery, 2nd opinion recommended hybrid lumbar fusion. What should I do? Daily pain 6+/10 back & both legs 2yrs

Be careful. Make sure seeking advice from well-trained spine surgeon. The pathology you mention will not necessarily cause the symptoms you list. Let's say you have herniated discs/lumbar stenosis, nerve impingement, then that will explain your leg pain. And after failing appropriate conservative management decompression surgery will help. But be very careful with surgery for back only pain -- [email protected] 23Y.O.
Bed rest. You should try bed rest for an extended period of time, up to 2 weeks. If symptoms improve, you're good. Otherwise, you get to choose what to do.