Marriage certificate in lucknow

Hi All, I just want to know few things about marriage certificate if I have to apply under hindu marriage act in lucknow if anyone has already done please help. I know procedure is online as well but it's very confusing literally . 1. What are the documents required? And all these doc's are required for both me and my husband? 2. Where it can be done? 3. How many witness are required 2 or 3? 4. Is there any extra charges while doing this? 5. How many days it takes to get it done? Please tell is there any prerequisites before we apply for marriage certificate? Please help.