Any low impact recommendations for when I can’t leave the house? I am in a lot of pain most of the time and putting pressure on my joints/feet/hands/back can be difficult at times. Swimming requires going out and I’m looking for options I can do at home on a bad day.

Firstly, i hope you get better. My recomendation would be, swim on as many good days as possible (but not more than 4 times a week). Learn relaxing in the watter (exercises on your back), learn to control your body in the water (exercises which include pelvis movement). That will help you get the blood flow to problem areas, strenghten your musceles and finaly you will enjoy your swimming more for it is going to be less exausting. If you have time i recomend you look into total immersion. In my opinion their aproach to swimming is optimal.
For the bad days I recimend you make yourself a nice tea and try to relax as much as possible. Try some meditation while thinking. Just enjoy yourself and try doing nothing. The reduction of stress is going to lessen your pain.
I really hope you get better.
Kind regards

Restorative yoga practice that doesnt include weight bearing asanas, pranayama breathwork, seated excersize programs and meditation will bring comfort and peace

I'm not an expert, but maybe try some low impact yoga? If you do the exercises softly and slowly it shouldn't put any pressure on your body, I think

I think you could just relax. I had the same problem with my lower back an I had to stay home and during that period of time I did little things that wouldn't really involve my back. I'm really into art so I was painting I watched different series and movies. And everyday I would move around more often. So by the end of the second week I was back on my feet. It did hurt once in a while though. Its entirely up to you and what you are interested in, to decide what to do at home on that bad day

This depends on which joint is hurting you the most. My reccomendation is to go to physical therapy where they will give you exercises that will not only keep you fit but also decrease the pain in your joints. I personally have a syndrome which also makes it hard on my knees, but physical therapy helped a lot. But make sure you tell your doctor if you really need it.

Light yoga or restorative yoga. You can make it intense or use it as a way to keep yourself from being too sedentary. It’s also a lesson in, if you are not feeling well, what’s a good way to move. What feels good to you? What helps? Test your limits. Find your boundaries.

I use an app on phone called Yoga Studio to help motivate me when I don't want to leave the house. It's got different ability levels as well as time durations so I fit as little or as difficult as I'd like. Or I look for simple stretching, yoga, or pilates videos on YouTube.