nepalese from china to hongkong with chinese student visa. requirements ?

Dear, you need to apply for a tourist entry permit to go there if it’s for sightseeing purpose.
Firstly, prepare all the needed documents including copy of your passport, your residence permit in mainland PRC, the application form, a passport-style photo, proof of your financial support, proof of your transportation and accommodation arrangement, and your travel itinerary to HK. And then submit the application to Beijing Office of HK SAR government to apply for it. Or post the application to HK immigration department to apply. The postal address is as following:
Receipt and Despatch Sub-unit
HK Immigration Department
2/F, Immigration Tower
7 Gloucester Road
Wan Chai, HK