There are a variety of higher educational institutions in Japan which provide many opportunities for you to achieve your goal or dream. Then you need to learn about Japanese educational system, to understand the differences among all types of the educational institutions and find the most suitable one.
Surely, you must learn Japanese language as you know, because it is needed for livening in Japan. However, based on your expected major and the institution you want to enroll in, you may have to study other subjects such as mathematics, physics, geography and so on. Then we will recommend that you know outline of each of the necessary exams before you actually start to prepare for the entrance exams.