I assume they rent trucks for most of the Grand Prix but since England and Milton Keynes is the home of F1 teams most can drive to Europe ahead of a race weekend.
Edit: Yep, provided by DHL who are also a sponsor https://www.wired.com/2014/11/ship-f1-car-across-globe-36-ho...
We all, for example, made fun of Nikita Mazepin, many calling him Mazespin and such (and hated him for his personality etc.). Even that kid was better (in some ways) than a lot of non-F1 drivers with quite successful racing careers.
There are some embarrassing examples we all know, but I'd say 80% are really good, just not F1 (or 2, 3) level.
There's a certain set of specialty tools and equipment (also staff) that's required to support one car. Supporting two/three doesn't take too much more.
For quite a few years, my business provided race support for 8-10 kart racers. Space and logistics for transporting things was probably the biggest concern.
Also a fun fact on one of the businessmodels in racing: the team operates like a specialized car-rental service. They do everything, except drive. The driver has to rent the seat for a season, this is where the team makes money.
Then there's 2 or 3 drivers. Of these, one is talented, the others are there for their funds.