I understand that CAD drawing and sketch modeling can be used as tools to make money.
In this case, it is good for you to use your spare time to practice in some studios or be an assistant. You can practice your hands in the early stage and make money in the later stage. Very good. As for making some personal bills by myself, first, the level is not enough, but the experience is insufficient, which is very embarrassing. So I suggest going to some advertising companies, making renderings, and this professional company. Anything will do.