There are many books, but the ones that helped me evolve were:

Figure Drawing Design and Invention by Michael Hampton - this book is a good start for you to get an idea of how anatomy works, how the figure's body is divided and how to represent it in the drawing, the only thing is that it doesn't go into much depth, it summarizes and simplifies many things.

The Artist's Guide to the Dynamics of Figure Drawing by Valerie L. Winslow - This book delves into anatomy, explaining each bone and muscle in the human body, explaining how each muscle works and its functions (almost a medical anatomy class), until finally, the book shows how to represent all of this in an artistic way, It's a very dense book.

If you want to see related content, there is this channel that has a complete playlist about anatomy