Are there any theories of cultivation in Japanese culture like Chinese immortals? How do Japanese Shinto priests and witches practice?

Japanese cultivation system is basically based on communication and reliance. Of course, because of the special psychological reasons of the Japanese people, they call all the demons and monsters "gods", so that Japan's "gods" are countless (presumably bad wrath of God). Yin-yang masters are basically the evolution of the five elements of Chinese Taoism, mainly based on charms and incantations, to serve the ghosts and gods, along with physical skills, very similar to Chinese Taoist priests (but the ability to basically rely on the bloodline, ordinary people can not be practiced). Witches and priestesses, on the other hand, are similar to the Buddhist way of practicing, which is based on visualization, incantations (called "spirit" in Japan), and guided by special "magical tools" to exert power similar to that of a god. Of course, because of the so-called "kami" in Japan as mentioned above, basically there is a sacrifice or a price to pay, and often it is your own body or something else. (If you're interested, you can study Japanese mythology, which can basically be read as H-novels.)