Whether you are interested in Naturalization, US Citizenship or Permanent Residence through immigration sponsored by a relative. There are several ways to obtain citizenship:

• Naturalization

  Naturalization is the process by which U.S. citizenship is granted to a foreign citizen or national after he or she fulfills the requirements established by Congress in the Immigration and Nationality Act (INA).
  For more information, see USCIS Policy Manual Citizenship and Naturalization Guidance.

• Derivative citizenship (from parents or spouse)

  There are two general ways to obtain citizenship through U.S. citizen parents: at birth, and after birth but before the age of 18. Congress has enacted laws that determine how citizenship is conveyed by a U.S. citizen parent (or parents) to children born outside of the United States.

• Child Citizenship Act (CCA)

  The Child Citizenship Act of 2000 allows certain foreign-born, biological and adopted children of American citizens to acquire American citizenship automatically. These children did not acquire American citizenship at birth, but they are granted citizenship when they enter the United States as lawful permanent residents (LPRs).

   

sources: travel.state.gov & uscis.gov