You need your 2018 AGI from line 7 of your 2018 tax return in order to e-file. Your AGI is not on your W-2.
https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-access-my-prior-year-return/00/270...
You can get a free transcript from the IRS:
https://www.irs.gov/individuals/get-transcript
The other thing you can try, is use zero for the AGI. But if zero will not work then you cannot e-file. That means you have to print, sign and mail your 2019 return.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
