Differences Between Affidavit of Support Forms I-864 and I-134?

Given the facts, I don't think he need 601 as his stay is only for 5 months, so not subject to three year bar. I-864 is the proper form.

Is 181 days overstay after OPT considered unlawful presence?

After OPT expiry date you have 60 days grace time, your 180 days counts from the 61st day. If you are applying 130/485 based on marriage, I would...

Filing AOS from H1B to GC through marriage. H1B visa stamp will expire soon. Will this be an issue for travels?

You can use either H1B visa or Parole for re-entry. parole itself is enough to gain entry when your I-485 is in process.

Can i apply for citizenship?

Not required to renew your Green Card in order to apply for citizenship as long as you are maintaining your permanent residency.

When I can apply for citizenship

5 year from the date listed in the green card. When asylees get their “green card” it is backdated one year, meaning that they can apply for...

Use your US passport to avoid possible issues at the port of entry.

My sister got rejected once for tourist visa from Pakistan. Please help

No specific checklist. She must show social/economic ties in home country so that she will return back.

I am undocumented. I have a criminal history. Am I able to get a green card when I grt married to my fiancee?

You have not provided enough facts, did not mention whether you admitted upon inspection or not. Consult an Immigration attorney with all facts and...

How should I renew i-94 validity after renewal of passport?

You can call /or visit CBP deferred inspection for correction. In my experience cbp will not correct the i-94 if admitted based on your passport...

Hello, My question is related to H1 b immigration where I need some sort of clarification in my scenario.

Your question is not clear. as you mentioned "un utilized" i assume that you have not admitted in to US on h1b status. Anyhow, the H1B approval was...