Graduate students: In Japanese, graduate students refer to graduates from universities, but they are not the stage for formal university students. Similar to the domestic preparatory students, there is no formal student status, but there are still many international students studying this course every year, because they can meet professors and attend the course, although there is no credit. Then take the formal college entrance examination and you can become a formal college student. However, the risk is that the professor may not want you if he says he doesn't want you before admission, although most of them won't.
University: that is, undergraduate course. The undergraduate course in Japan is also a four-year system.
Language school: A language school is a place where you can learn Japanese. In other words, you didn't major in Japanese in China, but you made up Japanese in the cram school, but Japanese is far from being able to take all kinds of college entrance examinations and college entrance examinations smoothly, so you need to learn it. Japanese school is a place to help you learn Japanese. Most foreign students come to Japanese schools first, because it is unlikely that you will come to Japan to take the college entrance examination directly or at home, so you are all here to learn Japanese.
College: a school that offers many courses and skills, such as makeup and cake making. Similar to domestic junior college. But unfortunately, most of his diplomas are not recognized in China. But if there is no requirement for a diploma and you really want to learn some skills, a junior college will be a good choice.