can an adult travel to south america to get their passport their?

You need a passport to leave the U.S. So you have to get it first.

This question doesn't make any sense. You have to have a passport from your home country to travel to another country.

You should probably check with your country's embassy here in the U. S. and ask this question. In order to get into the country you would have to have a passport or visa. You can find your country's embassy phone number at http://usembassy.state.gov/ where they are all listed.

If the adult is leaving from the US, he/she would have to get a passport before visiting any place in South America. A visa might also be required depending on the country being visited.

they will need their passport before leaving the country. if a us citizen, check at travel.state.gov for the proper proper procedures. if a citizen of another country, check with that country's embassy or consulate.