There are thousands of people who wish to become US citizens and one can become a citizen of the country by birth or a person can become a US citizen if his parents are US citizens. The country also allows citizens of foreign countries to obtain US citizenship and such a foreign national who seeks to become a US citizen must go through the naturalization process. You cannot obtain citizenship through this process just by filling out forms and you will have to appear for interviews and take up tests. This process is quite lengthy and it might take a long time to complete.
Before filing your naturalization application, you must first make sure that you are eligible to file this form and if you feel that you qualify for US citizenship, file Form N-400. That is because a person who looks forward to become a US citizen must meet few prerequisites and must not be a minor below age 18. The number of days that you had spent outside the United States, over the past five years will be counted as you need to meet the residency requirements. If you had remained abroad for more that 6 consecutive months, you cannot file your US citizenship application and you must have lived in the American state in which you filed your naturalization application, for three consecutive months. If you have a criminal background, your application for US citizenship will not be considered. Moreover, you must not leave the country after filing Form N-400 and you must remain in America until you take the oath of Allegiance.
After you file your application, USCIS will inform you about your biometrics appointment and you will have to go to an application support center to submit fingerprints. Your application will be processed and you will be notified about your US citizenship interview. Meanwhile, you will have to learn English and prepare for your civics test. US citizenship test is considered to be more important and you will not be granted US citizenship, if you fail the US citizenship test. You must have the ability to speak and understand simple English and your ability will be determined during the interview by the way you answer questions asked by the immigration officer. You will be required to write and read few sentences in English and this will help the interviewer to test your writing and reading proficiency. You must also have knowledge of the fundamentals of the US laws, history and government and you need to know about the country and its laws to pass the civics test.
You need to get through both these tests and if you fail in either one of these components, you will be allowed to take the test again but if you again fail, you must start the US citizenship application process all over again. Apart from all these, as a prospective US citizen, you must be attached to the principles of the US Constitution and you must not have a criminal background. USCIS will send you a ceremony letter and the date of your naturalization ceremony will be printed on that letter. You must attend that citizenship ceremony and take the oath of Allegiance. Finally will be granted a naturalization certificate.