The Greek meaning of Deuteronomy is second law and this book recaps to the new generation that will be entering the promise land, the laws that were giving to the Israelites that left Egypt. Their is a warning to them to obey the law.
Deuteronomy also recaps the travels of the israelites thru the wilderness. The Lord showed his love by providing for them protecting them, and taking their descendants to the promised land although he called them stick stiff necks because of their lack of trust and disobedience.
Deuteronomy also details the blessings that you will have if you follow the Commandments and obey God and the curses that you will have if you disobey. It’s all up to the individual.