How do I change the answer to the question asking if I lived outside the US for 6 months. I haven't submitted my return, but I know I answered it wrong

Go to My Info and click your name and go through the screens again.

That didn't work

To call TurboTax customer support

https://ttlc.intuit.com/questions/1899263-what-is-the-turbotax-phone-number

They are available from 5 a.m. to 5 p.m. Pacific time  Monday-Friday