You should have some familiarity with knitting in the round. Mercedes covers the basics of casting on with circulars and double-points for the class projects but she doesn't cover circular knitting in depth. If you'd like a refresher on circular knitting, try Stefanie Japel's Knit Lab: In the Round.
Whenever you're ready! The lessons are available online any time, and your access to the class never expires.
As long as you need! Your access never expires, so you can come back again and again.
Ask your questions on the platform and you'll receive instructor feedback. Your fellow students are also likely to jump in and offer advice from their experiences.