If you and your spouse filed a joint return the AGI is the same for each of you. It can be found on line 7 of your 2018 Form 1040. If you filed married fling separately, then look at each Form 1040 and use the amount from line 7 on each return.
Ok let me rephrase...how do I find my wife and myself individual income for 2019?
Look at the 2019 Form W-2 and/or 2019 Form 1099 you each received for your individual income in 2019.