US Immigration from China

I'm currently filling out the I-864 for my wife who came over on a K-1. I need some help with part 6.
1) For my income in Q7, I put the total income I get from the military, including my BAH. However, my BAH is not taxed.

2) My income for Q24, my income for the taxes shows an amount lower than I put in Q7 because of my BAH

3) I have filed taxes for 2019 & 2020 because I was in school for 2018.

4) My income for 2019 was below poverty lines because I only came on Active Duty in November.

My questions are:

1) For the income in Q7, should I only include taxed income?
2) I have a verification of no-filling from the IRS for 2018, will that suffice?
3) How many years of income are required above the poverty line to meet requirements for the I-864? (They say you only need 1 year but then ask for 3 tax return amounts)

I've tried reading the instructions on this but they don't seem to clarify exactly. I would appreciate any help! Thank you.

Hello!

Not sure if this is the right forum, but my wife came to USA as a K-1 Visa and we are married. What's the next step for us? (sorry if this question has already been repeated)