Paris Charles de Gaulle Airport is one of the main not only in all of Europe but also in the rest of the world. It is also known as Roissy Airport and is about 25 kilometers northwest of the city. Along with Orly’s, it is one of the most used if you arrive in Paris, especially if you do it on a low-cost airline. It has 3 terminals (T1, T2 and T3) and T2 is so large that they have had to divide it into seven parts to be able to accommodate all the traffic it has.
If you are going to arrive at Charles de Gaulle Airport, make sure that you do so at the terminal as this way you will be able to locate yourself and organize your departure in advance. There is a train that connects the three terminals completely free of charge, so if you are going to be at this airport only as a transfer to catch another flight there will be no problem and you will be able to move quickly from one to another. This shuttle train runs every 20 minutes and takes a few minutes to complete the journey.
If you want to go to Paris , you can do it in different ways. On the one hand, there is a commuter train (the RER) and also TGV or Thalys trains, with which you can even get to Brussels. You also have several buses, minibuses and taxi services, as well as being able to rent a car. If you are going to take the train, know that they leave every 10 or 15 minutes, the ones that go to Paris, and it takes about 25 minutes to get to a station in the city center such as "Gare du Nord" (I was in It was last year and it is very easy to go from there to any other point in the city).