Here are some resources which may help you improve the accessibility of Moodle, and accessibility in using your computer in general. They can be useful to anyone but may be particularly helpful to those with a sight or hearing issue or those who have dyslexia or a learning difficulty.
This is a tool for PC users which allows you to change the colour of the background and text of your screen. You can also personalise the tint of the screen. Download it by searching for it online or here: http://ssoverlay.software.informer.com/ Also watch the video below on how to use it.
This is a similar tool for Mac users. This app allows you to personalise colours and tints as above. Download from the App store or search online for Nocturne Software for Mac. You can find more information and reviews on the app here: https://nocturne.en.softonic.com/mac.
For use by both PC and Mac users, this tool uses your location and time of day to automatically readjust the light and bright.ness of your screen to optimal settings. More information here: https://justgetflux.com/.