If you became a conditional permanent resident because your immigrant parent married a U.S. citizen, it's possible for you to get the conditions on your permanent residence removed and receive a long-term U.S. green card even if your parents divorce. In most cases, that means you can and would file your own Form I-751 with USCIS, rather than being included on your immigrant parent's petition.
You won't necessarily have to file your own I-751 petition to remove conditions if your conditional resident parent gets divorced and files his or her own petition requesting that conditions be removed. (A divorcing immigrant can, in some cases, file the I-751 without the help of the U.S. citizen former spouse.)
Your conditional resident parent can just include you on the I-751 petition to remove conditions, as long as you became a conditional permanent resident at the same time as your parent, or within 90 days afterward.
Whether U.S. Citizenship and Immigration Services (USCIS) will agree to remove your conditions will depend totally on what happens with your parent's petition. To learn what your parent will be doing when he or she petitions, see I-751 Waiver for Conditional U.S. Residents in a Divorce.
If your parent's petition with you on it gets denied by USCIS, it might still be possible for you to successfully petition on your own to remove the conditions on your permanent residence for one of the reasons discussed below.
You are going to have to file your own petition to remove the conditions on your permanent resident if you became a conditional permanent resident more than 90 days after your parent did. Also, you can file your own petition if you became a conditional permanent resident before that but for some reason your parent doesn't file his or her own petition or doesn't include you on that petition.
One way to get the conditions removed from your permanent residence is to show USCIS that your parents are already divorced, and then prove that their marriage was real when it happened, not a fake marriage just to get your non-citizen parent a green card. You'll need a copy of your parents' divorce judgment and a lot of documents to prove that your parents' marriage was real.
Getting the documentation for a petition that relies on divorce will be really hard without the help of at least one of your parents. Your parents are probably the only people who have documents proving their marriage was real. Also, their divorce must be final and you must get a copy of the divorce judgment. If one of your parents filed for divorce and the case is still in court, that's not good enough.
If you can get the necessary documents, you will fill out and send a Form I-751, Petition to Remove Conditions on Residence, to USCIS along with the documents, a copy of your conditional green card, and a filing fee or request for fee waiver. For help with filing the I-751, see Filing a Petition to Remove the Conditions of Residence.
The important thing is to request a waiver of the "joint filing" requirement, so you can file on your own. ("Joint filing" means normally you have to file the petition with your U.S. citizen parent who is still married to your other parent.) In Part 3 (of the 12/02/2019 version) of the I-751 form, you put a checkmark in box 1d only. It's confusing because the form doesn't have an option that covers your situation. You want to say you're filing because your parents' marriage was entered into in good faith but the marriage was terminated through divorce. Box 1d. is the closest to that.
In Part 4, you check box 1b. and give information about your U.S. citizen parent.
If your parents aren't divorced yet, but you think they will be soon, you might want to wait for the divorce to become final and then file the I-751 with a request for a divorce waiver. If you don't want to wait for the divorce to become final, there are two other ways you can get the conditions on your permanent residence removed.
One option is available to children who have been battered or subject to extreme cruelty by one of their parents during the time the parents were married. If you can prove what happened to you and that your parents' marriage was real, you file the I-751 and check box 1f in Part 3 (12/02/2019 version). For help with this type of petition, see Filling Out Form I-751 With a Waiver Based on Abuse or Battering. That article is written for abused spouses, but the same advice applies for abused children.
The other option is to prove that if you can't get the conditions on your permanent residence removed and have to go back to your home country, you will suffer "extreme hardship." If you will suffer extreme hardship, you don't have to prove that your parents' marriage was real. When filing the Form I-751, you check box 1g in Part 3 (12/02/2019 version).
For more help with this type of petition, see Filling Out Form I-751 With a Hardship Waiver.