The forms can be obtained free of charge but you need to pay processing fees to USCIS.
tax forms that require and confirm proof of US citizenship
If you apply for citizenship in another country your US citizenship is automatically revoked. The US does not recognize dual citizenship. You revoke it in writing at a US embassy, outside the US.
Yes s/he can sponser a spouse. For the method please refer to: http://www.cic.gc.ca/english/information/applications/fc.asp As far as giving up citizenship: it is not required that the spouse give up citizenship. The US basically considers the spouse a US citizen and if they have citizenship in another country that is irrelevant to the US.
Yes, The residents of US territories have US citizenship
No, current US Citizenship form fees and biometrics(fingerprinting) is $675.00, Permanent Resident(green card) is $450.00. No lawyers are required to fill out the forms which you can download from the website and there is free help from USCIS in filling out the forms, and some qualify for fee wavers.
Yes, they are available in the related link.
NO! US citizenship is NOT automatic. Under these circumstances generally the child is entitled to and will be granted US Citizenship, but it is NOT automatic. You still have to obtain and complete the required forms and submit other paperwork and pay an application processing fee.
The US recognizes dual citizenship.
No. The US president MUST have US citizenship only.
India does not allow dual citizenship. But you can apply and get a passport-like booklet, at the nearest embassy and consulate general, that will allow you to travel to India visa-free.
If you are born in the US you obtain US citizenship by birth. Another way to obtain citizenship is through the naturalization process by applying for US citizenship using Form N-400 if you are eligible.
Yes dual citizenship is allowed for US citizens.