Oh well anatomy is probably the things im most proud of, i may not be the best, but i like to thing i know how to defend myself in the field
first of all things was learning how to approach figures through semplification of figures, looking out for parallelism (this helps with composition too) and gesture drawing, most of my thumbnails are in simple quick gestures so that i can later fix by taking reference pics and placing everything correctly through the aforementioned techniques

My most suggested books to learn anatomy as in a more detailed aspect are anatomy for sculptors and morpho, i used many other manuals, so i suggest looking up also dynamic anatomy (which is a serie of books with also dynamic figures and drapery) and anatomy for the artists

For drawing hands i use the same concept of stylization mentioned before, i look for parallel points for junctures and lines between arm and back of the hand that look harmonious and as close to the reference as it can, then detailing everything out of the basic shape