Yes, he can file. But, you may have problems with his need to show financial sponsorship.

How many years to get a GC when mother files for her married son?

Depending on your nationality there is a 12 to 25 year wait.

Can I work for an Indian company, paid in Indian currency into an Indian bank account while in the US on H4 visa without EAD?

No, this is completely forbidden. You will be sitting at a computer on a chair in the US ... thus you will be working in the US without...

How does h1b revocation affects h4 status?

Her H-4 is not connected to your employer, it is connected to you. As long as you stayed in current/valid H-1B ... her H-4 remained valid.

Can I apply to OPT if my 485 is pending?

Renew your 485-based EAD ... do NOT file for OPT.

When can I start my citizenship process and what are the documents I need to submit with my N-400 application?

I agree with my colleague ... wait until December 2021.

This might work. As my colleague mentioned, CIS is revising/reviewing rejected applications.

Affidavits from parents are a start. Get grand parents, aunts/uncles and even neighbors .... especially important will be the doctor, or midwife.

Is there any alternative way to get the R1 visa without appearing in the Consulate since the normal service is suspended ?

No, only a US Consul can place visas in a passport.

Q: 1. Does Primary applicant will get Two Biometric appointment? A: Perhaps Q: 2. Does Primary applicant will get Two EADs? A: Perhaps Q:...