Well if my parents files a petition for me while im over 21 years of age on permanent resident card.how much?

Question

how much time it will take for getting my immigrant visa>

Answer 1

I would say 2 days coz i have no ida :))

Answer 2

If your parents have green  cards and you are over 21 and married, that would fall into the F2b family preference category. for most countries, that would mean a wait of about 9 years. If they're citizens then the wait would be over 6 years. You can check it out for  yourself by looking up the Visa Bulletin in the immigrant visa section on travel.state.gov.

Answer 3

Are you saying that your parents are on green cards but you are not?  If so, it will be at least 3.5 years before you will be processed.