Over Stayed on visitor visa

[immihelp]

A person who lives in Argentina comes to US and overstays their visa limit. They are sent home once caught up with.

After spending 5 years back in Argentina, they want to become a US citizen. Is that possible, and if it is, how would a person go about getting citizenship?

Also, if the Argentina citizen was to marry a US citizen, would that cause him/her to get citizenship, or not?

[immihelp]

You can not directly get US citizen. You need to first get the green card.

Look at https://www.immihelp.com/family-based-greencard/index.html for marriage based green card.