Be born in the United States
Regardless of if your parents are citizens, if you are born on US soil the 14th amendment and Jus Soli likely give you citizenship
Both your parents are US Citizens
If one parent is a US Citizen and:
They are married at the time of birth
The US citizen must have lived in the US for a total of 5 years
If a parent naturalizes their children can also be eligible for citizenship if:
Child is living in the legal and physical custody of said parent
The child has lawful permanent resident status
Naturalization while holding a Green card
You must hold a green card for 5 years (or be married to a US citizen)
You must take a civics test (you can try your skills at the test here)
Demonstrate good moral character
You can find more information about all these paths here
This status is often referred to as having a Green Card. You may work and live in the US but cannot vote, Hold some government jobs, or serve jury duty. You may recieve a Green Card if you:
Are the spouse, child or parent, a a US citizen or Green card holder
Work for the US military during peace time (gaining employment as a non citizen is tricky)
An employer can sometimes offer a green card
If you are a refugee or seeking asylum (this is also heavily conditional)
The Diversity Visa Lottery
basically a lottery taking random people who have applied and selecting a few
the chances vary from 4%-1.3% depending on where you are from
There are a few options to obtain citizenship if you are an undocumented immigrant
if an Immediate relative has lawful entry
If a spouse, unmarried child (under 21), or parent has entered legally and obtained a green card the undocumented person can apply for a green card
only applies if they entered at one point legally with documentation and met with an immigration officer face to face
there is a waiver that can help to navigate if the undocumented person entered without documentation or meeting an immigration office but it is complicated
This is also how marriages between an undocumented person and a citizen can give them citizenship like what B and G are planning on doing at one point
If you have received Higher Education in a specialized field you may be eligible for some protection under the LIFE act of 2001
If you can file for asylum status
If you have been the victim of trafficking or another violent crime and helped law enforcement you could be eligible for a U Visa which could lead to a green card
This is supposed to help motivate victims of these crimes to help law enforement without fear of retribution
Being of victim of the following crimes could make one eligible for a U Visa: Abduction, Abusive sexual contact, Blackmail, Domestic violence, Extortion, False imprisonment, Female genital mutilation, Felonious assault, Hostage, Incest, Involuntary servitude, Kidnapping, Manslaughter, Murder, Obstruction of justice, Peonage, Perjury, Prostitution, Rape, Sexual assault, Sexual exploitation, Slave trade, Torture, Trafficking, Witness tampering, and/or Unlawful criminal restraint.
If you entered prior to 1972 you may be able to register as part of the Registry Movement and obtain a green card.