There are many books, but in the end this can't be thought in a book. Bodhipath is probably a good place, they also have lots of online things to read: https://bodhipath.org/.

It's more focused on the compassion part. The mystical is something which is easy to find online, but hard to find someone with the experience.

But there are different schools, more focused on study, mediation etc. Some are more formal, others informal.