Our school has this course, and I just finished it last week. As long as you are an animation major, you should have this course, because it can help you understand cartoon characters in all directions and is very useful for your modeling. Just like there are many three-dimensional figures now, they are all made of clay, then scanned into 3D, and slightly modified.

If you study, I suggest you start with the head portrait, step by step, and then buy a skinner's plaster to pinch it and feel his muscles interspersed. Understand the bones and muscles of normal people, no matter how deformed. Sketch is also important. It's good to draw when you're free. I hope this helps.