What level of Japanese can you realistically reach in three years of learning ?

Hi everyone,

I wonder how good you can get in Japanese on the basis of Japanese classes, 4 hours a week, during three years (considering I would study Japanese outside of class too, at least 30 minutes per day). I can also go to Japan for a student exchange in year 2.

Edit : I already speak French and English fluently. I have some knowledge of other languages but not fluent at all.

I would appreciate an answer based on A1 to C2 levels or JLPT levels. Thank you everyone !