Walk to the shops and carry your shopping back home. It exercises many groups of muscles. I was doing it long before experts were recommending it. Does that make me an expert?
Just walking is good for you. Get a walking app on your phone and try to do at least 7,000 steps a day. Simply weight training, like pushups are great. If it's difficult at first, do it with your knees on the floor until you build up strength. Planking is good for strengthening muscle groups throughout the body.

I’ve had to try this because I’m not as flexible as I’d like to be. Used to have something from the Canadian health organization that was good but couldn’t find it.

I’d try this out though, because it’s similar.

https://ehs.yale.edu/sites/default/files/files/stretching-techniques.pdf

Yoga is good for strength and flexibility I have been doing it for over 25 years after a major leg injury and back issues

My physio gave me something called The Core Mobility Series. Set of isometric exercises. So long as I actually do them I have zero back pain. I am 60 and work on a computer all day

I do a variety of things to help chronic back pain and sciatica.

Most are really yoga poses like cow, cat, cobra etc

I have the same issues and find that yoga helps, you can find videos on youtube for beginners☺

Try ddp yoga. I love it. You don't have to do all of it. ( There's cardio) But the yoga is great

I wouldn't know but i heard fish oil is a good supplement and cold makes sore joints worse?

best stretch ever. do both legs one at a time and really explore the stretch. hold at least 30 seconds, 60 is better

Stretching. Lifting weights.