ITIN for parents

You could apply but the IRS will likely decline the application.

Can I get offered a full time job and get sponsored for a US Green Card, based on employment by a Business owned by an Uncle?

It is possible,m but any blood relationship between the Petitioner the worker must be fully disclosed and you could expect the case to be viewed...

I'm a p1 visa holder and want to bring my son who is minor to visit me. what are requirements to bring him over?

He would need to apply for a derivative visa with proof of the relationship and your maintenance of status.

Can I return US in the future if I give up the pending Asylum application before interview?

It is unlikely that you would be issued anotheer nonimmigrant visa.

I got my mailed forms back from the USCIS in other to include the missing form and add the fee for the missing form

You should be able to add any missing forms and return the entire package with one check for $1490.00

This depends on whether an employer is seeking your services or you would be self-employed, among other factors.

Recover time in transition from H1b to F1

This depends on whether you have maintained status and whether you could be eligible for a new 6 years in H-1B status at this time.

Using old H1B and AC21 regulation - what is AC21 regulation?

Time can be recaptured if you are not eligible for a new 6 years at this time. Consult with an immigration attorney.

What happens to an existing B1 visa (Tourist) if the green card application is not successful

The visitor visa would be cancelled and an intending immigrant will not likely be issued a new visitor's visa.

Get legal residence permit to live and to help my 84 years old Great-Uncle in the US?

You cannot acquire status solely because your relatives need help. Consult with an immigration attorney to discuss your options.