How can I make a disabled person fully able to do their own work independently?

This depends on what the work is and what the person's abilities are. Some people can do it all themselves, some need support on learning it and are fine then, some will always need help doing it, and some people can't do it at all. It greatly depends. Ask the disabled person what they think they can manage, and what type of support they might need. Often, it involves the help of a disability expert. Let the individual and their team (if there is one) figure it out, and don't push too hard. Sometimes people truly can't do things, or it would be dangerous to try, or it would take too much energy that they need for other things.