I'm just a hobbyist passing through, but the go-to introductory books would be James Kugels' How to Read the Bible and Richard Friedman's Who Wrote the Bible?.

An important concept that you'll hear a lot about, and may thus want to research independently, is the Documentary Hypothesis, which is the prevailing explanation of theTorah having been compiled from 4+ original sources. This suggestion is more of a reference book, but Oxford's The Pentateuch might also be a good resource.

If you are up for watching videos, this Yale Intro to the Hebrew Bible class is an excellent introduction.

If this isn't what you had in mind, I'm happy to brainstorm some other ideas.