How to solve the traffic problem when traveling to Europe?

You can bring a portable WiFi and rent it. I booked one online when I was traveling abroad before, and then I went directly to the airport to pick it up. In addition, when going abroad, there is also WiFi abroad. If you really don't want to rent a portable one, use WiFi where there is WiFi, and you don't need to look at your phone all the time. After all, the main task is to play.