Dear Tony,
How do you choose where to begin? It admittedly can be very tricky.
I've said it before: Start with what you can do, not what you most need.
That sometimes can be difficult to figure out.
Any positive change is a step in the right direction. If you had skills which you lost in the last several months, try to start there. It is often easier to re-gain skills. Somehow our subconscious seems to hold on to them for a while.
Another possibility is to look at something you already do well and try to make it still better. That might be difficult to do when you have other problems. But it is still a positive change, and every positive change is good.
The most important piece is not the change itself. It is learning how to make changes and adjust yourself to changes. That may well be the most difficult skill you ever need to learn. But once you learn how to make your life better your life will become better. No matter how small the changes are.