How do you feel when meet international students from Japan who can’t conserve with you fluently in English?

I’m 18 years old. I’ll study abroad in US summer of this year, it will last about 4 years. (Around SanJose, California) (2 year community college, after that I’ll transfer to university.) (I’ll major in CS)

Now, my English skills is terrible.
I started English practice last year September, but it’s too late.
If someone listen my English carefully and allow me to speak English slowly, and ask “Could you repeat?” repeatedly, I can manage to communicate. Moreover, I probably can’t receive good scores on school.

But, of course I can’t speak fluently, so I’m anxious. Please give me your honest opinions and feelings.