Hi I booked my ticket to China on 15/4 after 15days but I didn't know that I need a visa

Dear, UL refers to University of London, right? So you mean you are from UK? If yes, you need to apply for it and you can apply for a tourist L type to see your boyfriend. You should apply for it as soon as possible.

You don’t need to provide the bank statement. You can ask your boyfriend to write an invitation letter to you. In this way, you don’t need to provide the round trip air tickets and hotel booking record.