Can I get a Green Card after a possible fraudulent marriage?

First, it is unfortunate that you put yourself in a situation where you entered into a fraudulent marriage in order to obtain your lawful permanent residence. Engaging in any kind of fraud is illegal and can lead to criminal charges and civil sanctions...not to mention that it is just "not the right thing to do." I hope that your previous experience particularly coming close to getting into real immigration and criminal trouble has made you think about the choices you make. Now, that you have a child with a USC citizen, you owe that child to be a ethical and law abiding father. That said, if there were never criminal charges filed against you for the fraudulent marriage and there were no specific immigration finding that you engaged in fraud by entering into a fraudulent marriage to obtain the benefit of your permanent residence then you can try to adjust your status through your USC spouse. Your USC spouse would have to file a family based petition (I-130) to immigrate you. Once the visa is approved then you would have to file the remaining applications to adjust your status to that of a lawful permanent resident. Depending on how you initially entered the United States, you may or may not be able to adjust your status in the U.S. Given your past immigration history, I strongly urge you to speak with an immigration attorney to obtain further guidance. My response is limited by the few you provided so if there are additional factors that I am not aware of, my advise may change. Thank you.

You should be fine as long as you withdrew your application (and it wasn't denied because of a fraudulent marriage). You should be able to refile based upon your new bona fide marriage.

When it comes to obtaining immigration benefits of any kind, issues with fraud or dishonesty are certainly an issue. Here, it is unclear whether DHS determined the marriage was fraudulent. Assuming there is no such determination, you may be fine. You will have to honestly answer any questions the government has regarding previous marriages, so there is still a possible red flag. Prior to submitting a petition of any kind, you may want to consider a FOIA request to see what's out there. Better to know the problems so you can know how to proceed.

Yes you can apply but you are likely to face additional questions and closer scrutiny because of the previous fraudulent marriage.

Possibly, although it may be an uphill battle with USCIS. The gov't will look at your previous marriage, petition and Immigration file, including any notes and/or reports contained in it from ICE. Based upon what's in that file they could question whether you gave false information in order to acquire a green card to the gov't in connection with your first green card petition and could deny your current petition based upon that information. I strongly suggest that you contact an experienced immigration attorney for a face-to-face consultation and give him/her all of the facts surrounding your case. He/she would then be in a better position to analyze you case and advise you of your options. Good Luck.

If USCIS has evidence to show that you have committed marriage fraud, you will be barred for ever to received green card based on even"real real' marriage.

Your green card application through your current bona fide marriage can be denied if the Immigration Service comes across compelling information that your first marriage was fraudulent. In this case it would not matter whether you withdrew your application. Getting married for the purpose of fraudulently obtaining a green card is enough to be barred from being approved ever.

Yes. As long as USCIS did not make a finding that you entered into a fraudulent marriage to gain immigration benefits, you should be able to reapply for adjustment of status. If they did make such a finding, you will also need to file a waiver on form I-601.