Will I be able to adjust my status if I used a relatives social security number in the past?

Adjusting status through your sister's petition is a preference case and not an immediate relative case. This requires you to show you have always maintained your status and never worked without authorization unless you are eligible for Sec. 245(i) and able to pay the penalty fee. You need to be very careful and not commit fraud on your application and answer all of the questions completely and truthfully or you will preclude your ability to ever become a permanent resident. I suggest a consult on your complete case, when you entered, what status if any you are in now, go through the facts of your entry , petition date, etc. If you would like a consultation on the facts of your specific case feel free to contact me as indicated below. I do charge for consultations but whatever you pay for the consultation would then be a credit toward the fees for your case if we are retained for services after the consultation.