There are many opportunities within Moodle to accommodate students with learning differences. However, if you're giving a quiz or exam in Moodle there is a particulularly easy way to accommodate learning differences!
The instructor will just need to click on the quiz from their course's main page.
From within the quiz screen, they'll click the settings icon like is shown below and click User overrides in the dropdown menu.
Click Add user override.
On the Override screen, they'll be able to search for the student(s) that they wish to apply the override to, and set the parameters of the override. They'll have the option to open or close the quiz at different times, increase the time limit or allow more attempts for the student or students that the override applies to.