Can I transfer my h1b immediately to different employer after approval?

Yes a new employer may file an H1B for you, without any required waiting time, if you have H1B status. Your new employer is responsible for filing...

Affidavit of support?

Yes bring evidence of your income to the interview. Review the instructions for the affidavit of support as to acceptable income of beneficiary...

Yes you may travel as B but you cannot be employed as TN

If my h1b is approved, if i still had time in OPT, can I withdraw my h1b and can I continue in OPT??

The employer may withdraw the H1b at any time. You do not need to seek H1B visa at consulate and it will eventually be canceled.

When can I get an answer on u visa case ?

You can check status as well as processing times on the USCIS website. If your case is outside normal processing time make a status inquiry with...

I am planning to apply for K-1 visa, however beneficiary country legal age to marry is 20 and my fiance is only 19 year

If the marriage is recognize in the place of occurrence it is recognized in the US.

Can you join the Air Force when my application for green card is pending?

You must be a lawful permanent resident or US citizen or national of the US.

How can i get my H4 stamping cleared which is currently in administrative processing under section 221g?

You have to provide the requested information.

I had the bio-metrics taken in March and still no invitation for the interview! ?

There is no limit on the time it takes to complete background checks.

No - the interpreter does not have to be the person listed on the application.