If you consider yourself a beginner in accessibility (like myself), I really recommend this learning path created by Mendix Academy: https://academy.mendix.com/link/paths/141/Improve-Your-App-Accessibility
From the general importance of accessibility, the different tools you can use, and hands-on practice to improve the accessibility of an existing app - this learning path covers it all!
I liked the learning module, I created a mp4 showing testing Mendix using Playwright, it works really well imo.
(145) Using Playwright within VSCode to Testing Low-code applications - YouTube