Shengyou school

Of course, you can take the exam. As long as you pass the Japanese exam, your grades don't need to be too good, but you must be good at Japanese. You must pass at least one level and then go to school to hone your acting skills. In fact, seiyuu is also an actor, so you should read more lines to hone your acting skills.

Of course, studying in Japan is also considered as studying abroad, so you need certain economic conditions at home.

Finally, I want to say that seiyuu rarely earns a lot of money in Japan, and even most seiyuu. Therefore, it is actually not recommended to go to Japan as a seiyuu

Now that animation in China is developing rapidly, there may be a professional seiyuu school soon (it seems that there are already schools offering seiyuu majors), so you can stay in China as a seiyuu and make contributions to the development of animation in China.