I've been living in the u.s for about 16 yrs.ive attended my 12 years of school and graduated and dhold my h.s diploma .im a good citizen

First, you must immediately stop referring to yourself as a "good citizen". If you make a false claim to be a US "citizen" for any government benefit, it could result in a permanent bar to permanent residence.

How did you enter the US? Did you have a visa, enter EWI or with false documents? What USC or LPR relatives do you have? What, if anything, was filed for your parents or you and when? Do you have a USC spouse or fiancee/fiance?

Your case could be very easy or very complicated. I recommend (not advise) you consult with an experienced immigration attorney. Many will give you good information over the telephone, but be prepared to pay a consultation fee to meet with them. Good luck.