Nice to see I'm not the only one to be working through HUMAN right now :D
If you're not familiar with the hair system in Blender, it changed right after Kent released this course (like literally... less than a month later). Kent was unfamiliar with the new system at the time, and as far as I know, no updates have been done, which is why he didn't cover it.
However, there's a section of the BASEMESH course that goes over how the new (since the HUMAN course was released) hair system that can walk you through how the tools work. Once you understand how they work, you can use Kent's techniques, adapted to the new hair system as far as how he talks about doing the hair. I'll be working on that in a couple of weeks, I think, so feel free to ask if you need help!