Hi Kris!
There is kind of a list called the Success Criteria, but honestly it’s not that easy to interpret. https://www.w3.org/WAI/WCAG21/quickref/

That said, there are a few easy actions you can take that make a huge difference to disabled people.

Install and run the Wave Chrome extension. This will only catch 20-30% of the violations but it’s a good start.
Make sure you have concise and descriptive alt text on your images. Write it like you’re describing the image to a person who can’t see.
Use headings (h1, h2, h3, etc) as a hierarchical structure (e.g., h1 is the title of the page, h2 are sub-heading of h1, h3 sub-heading of h2, etc.) vs a way to size your text.

Take those three actions and your site will be more accessible than most.

P.S. Never use an accessibility overlay plugin….NEVER, EVER, EVER.