Draw a hand
Draw self portraits or draw your favorite characters
tips that helped me draw photorealistically:
1. learn basic anatomy
2. get inspired
3. practice
4. study complex anatomy.
5. draw clothes slightly offset or larger than the outline of the body (quote i love: "man yall got sum super tight ass latex clothes or some shit")
in particular the book that taught me the foundation for 80% of what I know was "you will be able to draw manga by the end of this book"