I'm planning to married a my girlfriend in mainland

Dear sir/Madam
I'm from India I'm currently living in Singapore as a Singapore permanent residence. I planning to married in mainland after I want to stay there to work.also many years I'm doing trading from Mainland.
Kindly guide me following questions
1)I'm planning to start my business in mainland What visa can I apply
2)What are the documents I need to submit for my marriage.
3)can I make a marriage registration in mainland
Thank you