In your case, it is a bit difficult to go to Yokohama National University, but it is not impossible. Analyze it

1, Japanese students scored more than 500 points in the general national university examination (about 650 points in Yokohama National University).

2. TOEFL scores are generally above 70 (Yokohama National University is above 80).

3, Japanese proficiency test N 1 or above

4. Interview (the most important score, accounting for 60% of the total score, especially etiquette and language)

You still have time, you'd better work harder on Japanese and English. Come on, you will succeed.