@ victorcharlyze asked: "I didn't file taxes last year and it's asking for last year's AGI what do I do"
I'll assume you are asking in regard to verifying your 2020 return for efiling by using the 2019 AGI.
If you didn't file a 2019 return, then you would use a 2019 AGI of 0 (zero.)
TurboTax may ask you if you filed a 2019 return. If it does, and when you say "no", it may enter the 2019 AGI of 0 for you in the background. If it didn't, then you can enter it.