Due to the latest version of godot I am assuming that the practice files do not work?
When trying to follow this page and load the project I do not see a practice dock on the right.
As mentioned on the website banner at the top the courses are the only for Godot 3.5. You can see our roadmap to get more information about when new courses will be coming out: https://gdquest.mavenseed.com/community/15301-our-roadmap-for-godot-4-updates-to-courses
Until then we highly recommend following the courses with Godot 3.5.