What immigration process do I need to follow after marrying a non-citizen who entered the US on a tourist Visa?

You need to schedule a consultation with an immigration lawyer. The facts you listed above are not enough to determine if you are eligible for any...

Do I need to list a child that I believe is not mine when filing Form I-130?

You should list the child. You can always explain the situation at your interview if you have one.

Why did I get this update ?

Call the USCIS customer service number on your notices. They will be able to give you a better answer.

Do I need to file I 601?

You cannot file a 601 prior to triggering a bar. You should schedule a consultation with an attorney if you do not already have one representing you.

Contact the National Visa Center and explain the situation to them. The attorney cannot give you information about his client's case.

Have you already had your interview? If you have not, but the interview has already been scheduled, I would just let them know at the interview and...

CAN ME GETTING A CREDIT CARD RUIN MY CHANCES OF GETTING A GREEN CARD ??

There is no issue with having a credit card. There would be an issue if you claimed to be a United States citizen to obtain the card.

No, that would not simply be considered "negligible." When you later filed your 17-19 taxes, you should have addressed this issue. There is a...

Would I still be a risk of deportation?

Contact an attorney for a consultation. The information you have provided is a little out of order and requires clarification.

How to get a new Green card ?

More details are needed. Information like when your card expired and how long you were outside of the country is a good place to start. You can...