[saaxu]

Four years of high school Japanese isn't enough for you to pass the JLPT Level 1 Test. Four years is equivalent to being in the second year of university level Japanese. If you've studied hard and aced each Japanese class in high school, you should know between 90~250 Kanji depending on your school. Be prepared to take some Japanese courses at a university if you want to build fluency. High school courses are mostly busy work, so you won't learn enough useful Japanese until college.