They pretty much don't exist. In my 50-odd years of living in the UK, I think I have seen a drive-through exactly once. (It's in a built-up area a mile or two from Heathrow Airport.) I have never seen one anywhere in Europe. And I rarely see drivers eat or drink while driving. In some circumstances, the police may even take the view that you are Driving Without Due Care and Attention.

I don't even know if my car has a cupholder. There's an odd-shaped recess near floor level, between and in front of the front seats, with no obvious function, but I have never had reason to put anything in it. A cupholder is not a thing it would even occur to me to look for when considering a new car.

ETA: Having just been in it, I can see that the "odd-shaped recess" is indeed a cupholder. One learns something every day.