Although there is no score, I will give you an answer. There is no classification in CAD software. General CAD is universal. As you said, graphic design refers to two-dimensional graphics. It is convenient to draw plane graphics with CAD, but it is difficult to draw three-dimensional graphics. As you said, it is difficult to show complicated mechanical drawings with CAD software. If you use 3D, it is very simple, and you are familiar with the commands inside. Find more drawings to practice and read more books about this software, so you can learn it in a few months. If you want to master it, you must practice it in the factory. But now if you only learn CAD software, it is difficult to find a painting job. After learning CAD, you can learn more 3D software. As long as you learn this two-dimensional software, it is easy to learn other three-dimensional software. Even if you learn these softwares, you can't say that you have become a designer. I can only say that I can draw, I can draw. Only when you come up with your own ideas and draw them, and these products are not available in the society at present, can you count as your design. Remember to give me the rest after others agree with your work.