If you filed a Joint return for 2023 you enter the same AGI for each of you.
You need your 2023 AGI to efile 2024. The AGI is on 2023 1040 or 1040SR line 11. If you filed a Joint return you use the same AGI for each spouse.
How to find the AGI.
https://ttlc.intuit.com/community/agi/help/how-do-i-find-last-year-s-agi/01/25947
If you didn't file 2023 or filed it later in the year or mailed it, then try entering 0 for the AGI. If that doesn't work you will have to print and mail your return.
Or request a transcript from the IRS
https://www.irs.gov/individuals/get-transcript
