Taxi service from Civitavichia to the airport costs 120 Euros. Book here:
https://traveler.welcomepickups.com/en/rome/transfer/new?luggage=3&passengers=2&time=12%3A30&city=rome&property_id=&from=Civitavecchia%20Port%20&from_lat=42.092577&from_lng=11.792212&from_category=hub&from_address=Piazza%20Vittorio%20Emanuele%2C%2019%2C%2000053%20Civitavecchia%20RM%2C%20Italy&to=Fiumicino%20Airport%20(FCO)&to_lat=41.799887&to_lng=12.246238&to_category=hub&to_address=Fiumicino%2C%20Leonardo%20da%20Vinci%20International%20Airport&from_type=port&to_type=airport&from_location_id=18995&to_location_id=5089&partnerUID=