hi, im a student i need do study in hk, how can i get a student visa?

You need to apply a school in HK. Then you can apply if you prepare the required documents. The required documents are:
1. Filled ID995A form
2. A recent passport photo
3. A copy of your passport information page
4. Admission letter from the school you applied
5. If you are younger than 18 years old, you should provide the agreement letter signed by your parents and your sponsor in HK.
6. Accommodation proof (if you are younger than 18)