US Immigration from South Africa

Hello everyone, I'm really new to this site, I just recently discovered it actually, I wish I had known about it earlier in our process, and I have a question. So my wife was just documentarily qualified this week by NVC as we are working on her spousal Green Card immigration visa and she is in South Africa, so we are now waiting to receive her interview date.

So my question is for anyone who recently had an interview or is about to have an interview at the Johannesburg embassy; how long was it from the time you were documentarily approved until you had your interview date? Also how long after the email saying NVC had approved all the documents did you have to wait till you got the email stating your interview date? I am just trying to get an idea of how long we may have to wait from now till we get to the interview or how busy that embassy is. I would appreciate any information I could get from anyone! Thank you

Can anybody please tell me where to mail the I-129f form too after we've completed it

What section is applicable to K-1 one visa holder adjustment of status on form-i765?

I immigrated to the USA 3.5 years ago and my children stayed with their father abroad, I was going to settle for a year and then we would look at visitation. Before I left, my ex typed and we signed a maintenance agreement which was never filed at court, but he understood that it would take 6 months for me to be able to work and was gracious in that regard. When I arrived here, and looked at the job market I realized I would not be able to afford to pay him what I said I would (he typed the agreement up and said I must pay what he had been paying, but he had a corporate job and I have never had one). I kept in contact with him regarding this. AS soon as I got my green card COVID hit, and everything shut down. I was unable to find work until July last year (2021) and I sent him 25% of my income. I worked from home tutoring kids as that is what I have always done.
I am currently studying and my ex has refused to accept any money from me unless it is the amount he wants ($800pm). I can't send that, so I have opted to pay money to the kids school directly, which I have done all of this year.
Recently he got an attorney and said I owe a ton of backpay for the last 3.5 years, at the rate of $800.
There is no court doc stating what I should pay. He will not write a letter saying I have paid. I have all my proof of payments.
What on earth do I do for my application??

How do I fill in N-400 Part 9 if I'm filing after 3 years being married to a US citizen? It asks for total days outside USA in the last 5 years, but I have only been here 3.5 years.

Do I include the year and a half I was living abroad initially in my days?