I know there are already topics regarding flying on an airplane around this forum.. but I have a couple of more questions.

If my knowledge is correct.. people who are 18 and over need to show identification when flying.. is that correct?

well I'm 17 years old, but it is possible that the airport could think i'm 18. If they thought i was 18 and asked for identification.. what would i do?

all replies are greatly appreciated.. and if anyone had a similar experience (flying on airplane for domestic flights as a minor) please share. thank you!