How was Citizenship?

A citizen who are listed by the Government is commonly know as citizenshipA citizen get all the benefits from the country.

No. The parents have to go through the normal channels for citizenship with the INS.Another view: A child can sponsor green cards for the parents if the child is a US citizen above 21 years of age....

Yes you can receive both of his dual citizenship.

The U.S. Citizenship and Immigration Services (USCIS) Form N-600 should be used for adopted children residing in the United States while filing for a certificate of citizenship and USCIS Form N-600K...

Never.