It sounds strange to say, „I’m standing on a bus“, right? You probably imagine a person standing on top of the bus. But it’s correct. In English, we say we are on a bus, meaning to be inside it.
The same is true for some other forms of transport, too. We say we are on a train, on a plane, on a boat, on a tram, or on a motorbike. We do not say we are on a car though. We say ‘in a car’.
When walking, we either say ‘by foot’ or ‘on foot’. But one other key difference between English and Czech is that in English, we say someone is ‘in’ a wheelchair, not on one.
Here’s a short list to help you:
ON a bus, on a train, on a boat, on a tram, on a plane, on (or by) foot.
IN a car, in a wheelchair, and in a canoe!