I am studying in Harbin now, and my teacher will send me to Korea for three months in March next year. Hukou is in his hometown in Henan, and he needs a passport and visa. I need it.

Didn't the teacher send you to school? Then I'll say a few, passport, Korean proficiency test, you are an exchange student, you don't have to ask for anything at all. The school should do it for you, and it is impossible to ignore it. It seems that your English should be good. Haha, Korean universities actually look at English scores.