I track hit points, hit dice, and death saves in the Notes section, similar to Naatkinson.
I do spells differently than szemely, but similar in that I track spell slots in the same section. This screenshot is from my sorcerer:
Clerics or other characters that have a list of spells to prepare from are done a bit differently (the individually-listed spells are those from the divine domain and are always prepared):
My wizards are a combination of these two systems, where I'll have a list of spells that I've prepared for the day like my cleric, but I will also enter each individual spell like my sorcerer.