To become a U.S. citizen, most people have to become a lawful permanent resident first by applying for a green card. This process can vary in length, but for most people, it will take between 9 months and two years.
If you received your green card based on marriage to a U.S. citizen, you can usually apply to naturalize and become a U.S. citizen after three years from the date you received your green card.
For more information about the naturalization timeline and process, check out our naturalization resource guide.