The Kind of Book Where You Can Learn a Lot of Practical Knowledge for Free.

I want to read a book similar to "The Art of Testing Chinese Characters". Question: I read a novel. The realms in the novel are warlocks, human masters, earth masters, and heavenly masters. Then someone commented that behind the Heavenly Master there was a real person. I am interested in Taoist culture, but I don't know what the realm of real people is