BY AIR - it is a 45 minute flight from El Venizelos International airport of Athens
Aegean Air: https://en.aegeanair.com/
Olympic Air: https://www.olympicair.com/en
Sky Express: https://www.skyexpress.gr/en
BY BOAT - it is a 3-4 hour ferry ride from Piraeus (PIR) port in Athens, GR to Paros island (PAR).
If going this route, great to book your ferry trip after booking your big flight from the US to Athens GR. Keep in mind of travel time between once you land and taxi over to the ferry (30mins +/-) think of baggage claim, etc. Give yourselves a few hours in between if possible!
**Please note: the ferry waits for NO ONE! Make sure you are there a little bit before departure!
Seajets: http://www.seajets.gr/
Blue Star Ferries: https://www.bluestarferries.com/en-gb
Hellenic Seaways: https://www.hellenicseaways.gr/en-gb