I have my H1B visa and came to onsite from a indian company. Nature of work is not the one I wanted and I decided to resign. Am 3 months old in US with H1B visa. How should I proceed

You can simply return to India... because when you do quit... your right to work here ends with the sponsorship of that employer. THe condition of the H1B status.

Or you can contact the INS and learn that from them. What are the terms of your employment? Did they pay your way here, under what conditions will they pay your way back... can you pay your own way back?

After submit resignation, you have 7-10 days to pack and return to your home country. Your employer will have to notify USCIS, you don't have to do anything.