Your infotainment system would be what is connected to StarLink, Leo, or to whatever other network upstream.
The iPhone would connect to that.
Various vehicles already have similar features, though with terrestrial network connections, and not (yet?) StarLink or Leo.
It is conceivable that something akin to StarLink or Leo could be integrated into a vehicle. But that’s currently something for the vehicle manufacturers and the aftermarket infotainment vendors.
Based on a quick look, the StarLink High-Performance Dish or equivalent would probably be necessary here, and is (from what I can find) about 6 kg and requiring 100 to 150 watts of power, and seemingly priced around $2500 plus subscription.
Note: SpaceX StarLink and Subaru STARLINK are entirely different systems, with the latter being renamed.
Check with your preferred vehicle vendor.