Charles de Gaulle Airport Paris. London Heathrow is an option, hop on the Eurostar, it’s a quick 2 hour and 20 minute train ride into Gare du Nord station located in Paris

Best option, walk! Paris is a beautiful walking city, best way to see the sites. Metro is your best bet for quick travel around the city. Trains come every 3 minutes and the rail is very easy to use! Just be aware of pickpockets in busy areas