Question about Greencard process ?

Yes, she is eligible to apply for work permit with a pending adjustment application. Goodluck. Ekaette Lawyers

What can I do if I just recently found out my husband was married twice and after a quick google search I can't find any divorce

It is advisable to have a consultation with an immigration lawyer for viable options. You may be eligible for VAWA under those fact...

What are the valid options when 221 G issued for H1B Visa?

It is adviable to utilize the services of the company lawyer for a strategy. Goodluck Ekaette Lawyers

Is it required ex-husband's approval to bring the kids to the US?

This is best discussed with a custody lawyer in your home country. If she has legal custody she can travel with the children. Goodluck Ekaette...

Your eligibility to apply for a US passport is not impeded in any way. Goodluck Ekaette Lawyers.

This should be direct at a Social Security Lawyer. Goodluck Ekaette Lawyers.

Out of status. i 94 expired in Aug 2017 based on H1 b visa. Valid I 797 tillJuly 2018. Errorat POE by CBP. What do I do?

It would appear to be no error as you did not file in a timely manner. Goodluck Ekaette Lawyers.

Oath Taking For N-400 and N-600 held together? I have approved for a Certificate of Citizenship

The letter is intended to present you with your Certificate of Citizenship, and yes there is a ceremony. Goodluck. Ekaette Lawyers.

I got a NOID?

You have a lawyer and it is best to discuss your case with that lawyer who has all the facts at his or her disposal. Goodluck Ekaette Lawyers.

Your employer's immigration lawyer can advise on all your immigration needs. Goodluck Ekaette Lawyers.