Hej, I agree with others. 10 days per level is pretty reasonable.
As for your questions:
- schedule - yes, i recommend
- lessons - not too many at once since they will come back in waves for the many review states. some users go by 10 / 15 / 20 / … lessons per day. I usually do something between 12 ~ 24 depending on my mood
- and here is the ultimate guide everyone should peek in at least once
Good luck on your journey and have fun.