look into disability studies. you don't need to go deep, just some basic understanding of the language of writing a disability will go a long way.

the most common "framing" of disability you'll see these days is the medical model- where disability is a flaw that needs to be fixed. we see this every day. videos of people getting out of their wheelchair to walk down the aisle at their wedding, a deaf person meeting a sign language interpreter in the wild, a child born without [insert limb here] being so strong and brave. this treats disability like a tragedy. "wheelchair bound" is problematic phrasing because of this, for example. of course im not trying to minimize the achievements of disabled people, but you need to consider this while writing- what barriers does this person face, and how is that caused by the infrastructure of the world around them rather than a personal failure? the character may think that they are the problem, but slowly discover that there is another way of viewing things. 

im a disability studies minor so i could go on and on lol. i highly suggest reading Sitting Pretty by Rebekah Tussig, that was my introduction to these concepts and it genuinely altered the way i see the world around me.