We often see some lifelike portraits in patents, such as heads, expressions, hands and so on. What software are these drawn with?

Image processing software ~ such as CAD and PS

The most important thing about the patent map is that it can be understood by people, and the meaning of the image is clear. I usually use CAD to make patent drawings.

I apply for a patent for others.

If you can use a software well, that's good. You don't need to know everything, you might as well master a subject.

CAD is totally ok.