Bible study teaches the "documentary hypothesis" that cobbles together Biblical parts and attributes them to Moses.

Outside of faith-based universities, academic Bible courses generally teach that the “Five Books of Moses” (the Torah), were not written by Moses. They teach the documentary hypothesis, according to which, many centuries after Moses, an editor, referred to as R (for “Redactor”), cobbled the text of the Torah together from four (or perhaps more) documents.

Yet to this day, no one has found literary evidence for the existence of the “sources” that the redactor supposedly drew on. The documentary hypothesis remains a hypothesis.
So, who wrote the Bible?
A jewish scholar tackles conflict between biblical criticism and traditional beliefs about the Bible’s authorship.
https://www.jpost.com/judaism/ani-maamin-old-fashioned-beliefs-confront-modern-biblical-criticism-626431 (Listen or Read) from May 2, 2020