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First: Conditions for obtaining US citizenship.

In order to obtain US citizenship, you shall meet the following conditions:

1) Not less than 18 years of age.

2) Stay in America for 5 consecutive years, but if you are married to an American you shall stay for 3 years continuously,

3) To be in the United States of America, so that you may apply for the citizenship.

4) Provide proof of your good conduct.

5) Be able to read, write and converse in English.

6) Pass the American National Education Examination.

7) Perform the constitutional oath.

Second: Procedures for applying for citizenship:

1)      You should fill the N-400 form via the following link:

n-400

2)      and then print the application and submit it to the Department of Immigration and Citizenship of America to be attached to the application, your personal photo, a copy of your residence card.

3)      Your fingerprint will be taken in the administration you applied for, and your fingerprint will be sent to the FBI. If it is accepted, an appointment will be set for the interview.

4)      After the interview either your application to be accepted or refused. In the event of rejection you shall appeal the rejection.

5)      You need then to attend the naturalization ceremony.

In order to obtain the citizenship of a country without the residency requirement, this matter will depend on your financial capabilities, and here are some countries that you can obtain citizenship after paying the specified sums and some of which may require a fixed-term residence.

In response to your inquiry, you should review the answer through this link, which we were honored to ask the question at a previous time.
The link is: ANSWER