Doublepike

It will say what you have to submit (assuming you are doing it online, it's easier).  Some examples include your last 3 years of tax, green card, birth certificate of your US spouse, birth cert of your children etc. You can submit extra documents as well. Pretty much everything you already submitted for adjustment of status + all the new stuff.
I submited 60 documents in total and the Immigration Officer at the citizenship interview thanked me for making this easy for her because she was able to  approve me in a month and a half! 
 
Good luck, N400 is easy but still a lot of paperwork! 
 

Just had my interview yesterday in Oklahoma City, OK. 
I submitted my application on June 30th, got interview scheduled for August 15th. 
 
The IO was really friendly and nice. We did civics first, writing and reading next. After that we went through the application and basic information like my name, date of birth etc. I signed a few documents and she told me I passed and I should wait 2-4 weeks for ceremony to be scheduled! 
 
What a great experience and journey this has been! Ready to have the ceremony and be done with uscis once for all. 
 
My advice would be to have your spouse ask you the civics questions every day! 
Good luck! 

Yes, they were one of the first ones to blaze through. I was shocked to see their approval, but this latest one electrocuted me!
 

Hello everyone, Just wanna share my timeLine with you people!
 
Oct 12, 2021
1-751
Submission to USCIS
 
Mar 11, 2022
1-751
Biometrics, i.e. fingerprint and photo
 
Jul 21, 2022
1-751
Request for Evidence(RFE) from USCIS
 
Aug 20, 2022
1-751
Response to RFE
 
Aug 30, 2022
1-751
Decision (Approval )
 
Sep 08, 2022
1-751
Card was delivered to ME
 
wish all of you guys all the best for who still waiting,,,

Here it is! 

No norm!! My I-751 was approved in 2.5 months. I’m glad to see others are getting approved as well! 

We just submitted my wife's N-400 online under the 5-year rule.  Let the new wait begin!!!  I really hope she gets a combo interview soon. They owe us a favor.
BTW, filing under the 5-year rule was pretty easy.

Send the whole package! 

Here is my cover letter! I kept it as simple as possible! 

Well that was rather a weird assumption and accusation. Been here since 2019 just like everyone else. 😬

Acutally, August/September  2018.

So happy for you! 

Well that was rather a weird assumption and accusation. Been here since 2019 just like everyone else. 😬

Well that was rather a weird assumption and accusation. Been here since 2019 just like everyone else. 😬

Acutally, August/September  2018.

Well that was rather a weird assumption and accusation. Been here since 2019 just like everyone else. 😬

Yes! Here is the timeline! 👇🏻 
I have no idea why I got approved so fast. I was expecting to wait at least a year. 

Oh wow! I already sent mine (I'm a February filer) and was wanting to compare our packets. They're similar. Hope to get a fast approval soon. Congrats again!

Yes it’s correct!!! Well, aproval date says May 1st actually, I will post a screenshot below.
 I just I got an email on USPS informed delivery this morning that I am getting a mail from USCIS and I was like whaaaat I must have done something wrong it’s denied etc.. 😅 so I went to my Uscis account to see the case history and omg!! My card will be here today. And no I didn’t expedite. I was prepared to wait at least a year. Good luck to everyone! 
 

No, I don't "get that feeling".  Everything is ALWAYS Trump's fault??.......For your information, the world is in the midst of a PANDEMIC...which originated outside the US!!!!!    

Sounds like he's a good salesman too. 

Same answer as above. I applied a week after I entered US. Do things as soon as you can. Don’t wait on it.

This likely happens a whole lot more than we hear about it on this forum. I vaguely remember a couple of cases in the pass that were along the lines of the OP. This is an extremely difficult and embarrassing situation. I admire the courage of the OP to come here and discuss his options. But it also makes me wonder if he did it to get the 
 
I want to share a phrase I learned that should help you decide on what to do.... "Don't light yourself on fire to keep someone else warm."
 
You may love her, desire her, and she has a lot of things you want in a wife. But she may not be for you. You can love someone without being with them. There is no governing, spiritual, or physical law that states you HAVE to marry someone because your love them. Some times people are not good for each other no matter how they feel about each other. I'm all for giving someone a chance if they make a mistake. But this may be something that is beyond restoration in my opinion.
 
Here are things to consider:
You will be responsible for her and the child, even if you two divorce later. It is in the affidavit that you will sign for her. The bio father may want to be in the child's life and could very well have the right to say whether of not the child can leave the country. Having a child is stressful for any relationship. You two would be going from young loving newlyweds to a full family with huge responsibility and trust issues. You will not have given your marriage enough time to develop. The baby will multiply your financial expenses 10 fold. You don't seem the know the true nature of your fiance and the biofather's relationship. From your follow up post it seems you have little information about him. She may had some serious feelings for him now. Obviously, she has some feelings with him if she produced a child with him. But it could very well be more than a fling. This situation will put an extremely negative variable in your relationship. Immigration issues, assimilation issues, and financial issues are already waiting to put a burden on your relationship. Now you have to deal with trust and uncertainty. To answer your question, it is possible for you to go through with the K1. But there may be some tough questions during the interview. If you are there during the interview (and I HIGHLY suggest you be at the interview if you move forward with this), she will need to be 100% truthful. The interview is not the time for surprises to pop up. And those officers may ask some really tough questions.
 
 
At 31 y/o, you have to realize that life is just now starting for you. Don't start it off on the wrong foot. You have a choice to direct the path you want to take. You can start a successful business or backpack around the world if you wanted to. You can still care for her and be there as a friend to her. 
 
If you do decide to continue... at least make the choice to delay the interview. Tell her you need some time before move forward. Give yourself a few months or even a year before finishing the process.
 
I truly wish you the best of luck. And if I knew you personally, I would have a case of whatever your favorite beverage waiting for you.

This is painful to find out.
Supporting you and sending you energy with all my heart.

@payxibka, was that the fellow who joked to CBP about maybe not getting married?