Visa or Greencard?

It depends on your status. If you are a citizen, you can sponsor them for green cards.

I130/I485 (based on marriage to U.S.C.). Interview letter requests certain information I thought I didnt need to submit.

Yes you should take the birth certificate. CIS probably wants to confirm where he was born.

Hi, Iam on H1 visa and have my PERM pending at the moment.My visa expires in 1 month and I have to leave the country .

Wow! What a mess. You need to be able to speak with the employer's attorney to discuss your options. All of the above depend on your employer's...

Can I still renew my green card even though I have defaulted on my student loans and currently have no job?

Depends on the basis upon which you received your green card.

Can I apply for green card?

I suggest you speak with an attorney in private so he can review your information and advice you if you have any options.

My EAD from my OPT expire July 11th. My girlfriend and I are getting married June 30th. AOS filing July 17th. Can I still work?

You will need the EAD approved so you can work. EADs take approx 90 days.

If you filed EB3 and have only worked for the employer for 3 months, I am assuming it was for "future employment". Unless you work for the employer...

What steps do I need to take to to become a US citizen?

If your visa has expired and you are out of status, you have limited options for filing for green card or citizenship. I would recommend that you...

Yes you can.

I applied R-1 before OPT my expired. R-1 took long and fear of getting out of status, I applied for school again and got F-1

depends on which was approved last. That is the status you have.