Idk if this is helpful but I wanted to kinda answer @mothric's question, cuz I have a lot of spine and knee and bone issues and have also been to a LOT of physical therapy, and I think it can be really good to take some time to like...familiarize yourself with your pain, if that makes sense? Like I've noticed there is a difference between "this hurts bcs I'm working out" and "this hurts because I am Doing Something Wrong", I tend to feel the first type of pain in the muscles I'm working on, and it's like a warm or burning sensation, while the "oh fuck that's not good" pain feels sharp and very much located in the bones of the joints I have issues with. Like, you should feel it in your muscles, not your bones.
And like there's this idea that exercise is supposed to hurt, especially physical therapy, but the physical therapists that I've seen have been very clear that while exercise can "hurt" it shouldn't actually be extremely painful, and if it IS you should dial things back or just stop for the day to avoid injuring yourself. I've actually hurt myself pretty bad pushing myself too far while exercising(I ended up barely being able to walk for like...three weeks, it was Bad) and yeah if you start to feel pain in the joints you have issues with that is similar to your usual chronic pain you should really take a break.
Also, feel free to take days off in-between! You won't lose your progress if you rest, and at the start your muscles are def gonna be achey and it's a good idea to give em a bit to recover between workouts. My physical therapists would usually have me come in every other day, and do the big stuff on those days, and in between focus on smaller stuff at home. Breaks are good!!
Also also, while I'm glad people in this post have seen such a dramatic improvement after exercising, remember that not every condition is the same, and some of them genuinely will not improve with traditional exercise. If you're working out at home and you notice your pain getting way worse, or you're suddenly exhausted all the time, or you're just straight up not seeing any sort of improvement after a few weeks, def consider stopping and, if it's within your means, talking to a doctor or see if you can get in to physical therapy so you can be sure you aren't just making things worse.
So yeah, familiarize yourself with your body and your pain, remember that going slow and taking breaks is good, and if things get worse or hurt really bad you should absolutely stop.
Edit: I also know this isn't possible for a lot of people including myself bcs COVID, but if you can safely access a pool that's a really good way to get a full body workout without hurting yourself, since the water takes the weight off your joints. You really wanna go for low impact stuff, so swimming or using a reclined stationary bike, and avoid running. Running isn't as accessible and safe as people pretend it is, especially if you have joint problems.