Sorry, I didn’t read to the end! I’ve started working with hand weights for my arms and upper body, but I really need to strengthen my core. I’ll try the sitting ones and see how it goes.
I am in absolutely no position to comment on your medical condition, but since you allude to knee pain, I offer this anecdote.
I was able to alleviate chronic knee pain by strengthening my hamstrings; admittedly, weight lifting was involved, but stiff legged deadlifts (coupled with stretching) have alleviated pain that used to plague the front of my knees when I did deep bends.
It’s really arthritis (diagnosed), but I’ve been noticing a lot less pain since I’ve been losing weight.
Well, IANADr, or any sort of physical therapist, but building up the muscles of your legs is crucially important.
And I’m pleasantly surprised to see that the official recommendation includes my suggestion for “chair ups”.
Iif you’re inclined, see if you can - slowly, over a long months long progression - build up to deep knee bends. You’ll need to improve flexibility and strength, but if you can sit in the bottom of a squat, and then stand up, then you probably don’t need to worry about health risks associated with immobility.
It is undoubtedly possible.
Just to underscore my cite above, it says
So, although it might seem counterintuitive to some, now is not the time for people like @carrps and the OP to eschew strenuous physical activity, especially muscle building activities.
(My emphasis).
Note that most studies showing that symptoms are alleviated considered muscle strengthening, because that’s the most effective treatment. Sure, the OP can walk more, but that’s just the first step.
Eventually, you should start to challenge yourself. Your body will benefit.
Thanks for all that! Truly. But I do know that exercise is one of the best things you can do to alleviate osteoarthritic symptoms. It’s just building up to it. 
If sitting down in a chair and getting back up is hard work … it’s a hard workout. Do that, and do it repeatedly on a semi-regular basis. Etc.
A lot of the exercise advice & proselytizing and expectation-setting out there is tailored to the 25yos. Which can be real off-putting for elder folks or those with severe mobility challenges, obesity, etc.
All that matters is that you’re doing something repeatedly that is challenging for current you. If sitting in a chair lifting cans of Campbell’s soup over your head is hard, then that is exercise. Soon enough a can of soup won’t be as heavy anymore and you’ll have to lift something else bigger.
The early gains are the huge ones; the ones that lift you (any you) out of infirmity and into movement adequacy.
That was a kind remark for sure! I like the different ideas for walking and balance exercises described here. It’s amazing how a couple weeks can feel so good so am starting all ready.
I’ll start soon. I tried the squats already. I can’t go all the way down yet, but I’ve been having issues standing from a full squat for a while. I need to improve that.
It’s weird in the cooler I’m up and down a 3 step step stool, I lift cases of gator-aid. And it’s getting harder. Prolly 'cause I only work once a week now. Lots more issues with being on my knees and stripping off shrink wrap. I really hate shrink wrap.