If at least one of your parents was a U.S. citizen prior to your birth, you may also be U.S. citizen. “Derivative citizenship” laws and requirements differ and are based on the year of your birth. There may also be different requirements based on whether your parents were married at the time of your birth. If you are considered a derivative citizen, you may be eligible to apply for a U.S. passport and a Certificate of Citizenship.
After USCIS reviews your N-600Application, you will be scheduled for an Oath Ceremony during which you will receive your Citizenship Certificate which serves as proof of your U.S. Citizenship. You can also apply for a U.S. passport at that time.
If approved for a Citizenship Certificate, you are considered a U.S. citizen from birth for the remainder of your life unless you formally renounce.