hi sir, i want to get all kind of information about Hong Kong Visit and Business visa

You need to provide your valid entry permit to HK, your passport and other relevant documents to get married in HK.

You can enter with a tourist entry permit. Because if you apply for the business entry permit, an invitation letter from a trade partnere in HK is needed. The required documents for tourist entry permit include copy of your passport, a recently-taken half-length photo, the application form, proof of transportation and accommodation arrangement, and an invitation letter from your girlfriend. And then ask your girlfriend to submit the application to HK immigration department to apply for it. It usually takes 4 to 6 weeks for the whole process.