Have you considered trying Yoga too. I was stiff as a board, had a knee that caused some issues and lower back pain often. It's all gone now. I also stand more upright. I put on 9 pounds of muscle and lost 4 inches around my waist. To me Yoga is a miracle drug. I just do it in my own home, maybe 3 to 5 times a week.
People say they don't do it because they are not flexible. But that is WHY you do it, so you will become flexible. Learning to breath correctly will help in everyday life.
Lots of free stuff on Youtube. I have found I do best if I follow 3 or 4 instructors
One to look at that really has good stuff is Yoga with Adriene
https://www.youtube.com/channel/UCFKE7WVJfvaHW5q283SxchA
https://ddpyoga.com/ is where I got my start and I love the teaching methods. lots of success stories on the site from people who couldn't walk to super over weight and health issues.
I usually do 3 DDPs, 1 or 2 Adriene's a week. I would do more DDP but the old man kicks my butt.