Citizenship help!?

I went in yesterday for my interview and passed it! I was really excited until he pulled out my application and telling me I didn't even have to file N400 because I am already a US Citizen because of biological father. Now they're asking me to file N600 instead, and I have to provide my fathers certificate to prove he is a US Citizen already and the problem that I have is I need to provide some kind evidence that I was in his custody when we moved here in the US. I don't have any records of bills anything address because I was under age at that time and we did live w/ my dad for a few months only. So before I even started highschool here in Nevada I already lived with my Aunt and Uncle so I can go to the school that I want (bcause of the zoning). Wil a notarized paper saying I lived with my dad when we moved here is enough (w/ his signature so I can be naturalized? or is there anyway I can ask DMV to give me a paper copy of my State Id (My very first ID) from 11yrs ago? What are my other options?
Answers

Kathy Miller

Do you have any photos of you with you Dad when you were little?

W.T. Door

If your father was a US citizen when you were born AND he had lived in the USA for five years (two of which after his 14th birthday) then before you proceed with the USCIS procedure look into simply applying for a US passport. https://travel.state.gov/content/travel/en/passports/apply-renew-passport/apply-in-person.html