I wrote you a long reply based on my T'ai Chi practice for around 50 years, but this was lost someway and I haven't been able to recover it. I will try to remember what I wrote:

To summarize my medical situation:
I developed neuropathy and rheumatoid arthritis from frostbiting my feet too many times with skiing when I was younger. I kept forgetting how far it would be to get back home. I found neuropathic ulcers on my feet are aggravated by rubbing, so I got boots four sizes too large that are not that much wider. I massage my feet every morning with Vaseline intensive care and wear thick, soft ski socks. If the ulcers start bleeding I wash the sores with rubbing alcohol and put on a mild antibiotic cream and band aid only until the bleeding stops. My rheumatoid arthritis is progressing, but the autoimmune system is so unpredictable and erratic, it seems drugs are too risky, as what helps can later make things worse. This seems especially true with
the depression and anxiety that goes along with it. On this website it seems there are as many people trying to get off addictive drugs as people wondering what they should get on.

When I was learning to do T'ai Chi in a remote arctic community in Canada, I didn't have a teacher, there was then only the book with photos and feet position diagrams. This took many years of practice looking at the photos and trying to copy the positions. Later there were tapes and videos, but there is an issue with watching
someone doing T'ai Chi as they move in different directions, as you watch them and move from your own constantly changing angles. Years ago I was able for one time, able to join with a group. I was shy and stood on the edge of the group. This is a big mistake. When you are in a group, go to the center of the group. Then as you go through the movements, there will always be someone different you can watch to see how you should be moving. You can blend with their energy flow, and your body will learn fast.

They use the word "forms" for distinct positions. This is only partially helpful as you don't simply go from form to form. T'ai Chi is a fluid thing with continuous coordination of body movements and smooth breathing. Over time the "forms" are not the object. The goal is fluid, water-like harmony of mind, body, breathing, and motion.

It is good to practice outdoors, preferably on grass or sand. Cement blocks the connection with the earth. This goal is called "rooting". Everything has Qi or energy, of course obvious living things, like trees and plants, but the earth itself has an awesome Qi. You can detect Qi in a waterfall. The goal in T'ai Chi is to get to a point where your body knows how to do it, like touch typing, and you with your mind are in every way open to Qi from all sources. If you lose your balance, lower your center of gravity, bend your knees more and root yourself. Learn to walk with continuous rooting.
It is very good to do T'ai Chi in the morning outdoors when the birds are getting up and wildlife in general is active. They like to watch you, and they are your T'ai Chi best friends. Trees moving in the wind are great teachers to follow in your own way. I remember one time practicing on a flat rock half way up a hill. I looked down in the water below me and saw around two dozen black ducks in the water, all staring up at me. To me interactions like this show you are on the right track. It seems they take you as one of their own and everyone can become unafraid.

Once you get the idea of T'ai Chi, you can go freestyle. Seeing a tree moving with the wind, you can dance with it. You can swim with an otter. You can run with caribou or deer.

It is good though to learn one of the traditional T'ai Chi forms. Your body will learn it and take over, and you can observe different aspects like your breathing, rooting, release of tension, etc. , bringing everything up to the same harmonious level, like with a musical instrument.

It seems helpful to think of your body like a horse and your brain as the rider. I think it is best to use your brain to work on your brain. On this website it seems as many people are trying to get out of addictive drugs as those considering which ones to take. With the "horse and rider", the goal is an equal , balanced and harmonious partnership.. T'ai Chi promotes this very much. The brain can function at a much less hectic pace. T'ai Chi is not a mind game. The rider doesn't demand obedience from the horse. It is all about a cooperative interaction and building each other to their healthiest and happiest level, by lowering unnecessary things to a much less demanding energy level. Sounds contradictory, but it is never boring. Boredom is not healthy.