First of all thank you for the course. I think it is currently exceeding my skills, but I am learning quickly.
Since the “Sculpt Tools UI” is not available for version 2.8, can you recommend another method to continue this course?
If you mean the extract mask functionality of Sculpt Tools, yes!
Then (after confirming) you can can change the thickness here:
(Use the latest Blender version, when that isn't there yet.)