Marsupials are mammals – and mammals, at least one would think, are everywhere, including Europe and Asia. With the marsupials, however, it is different. They are a very special subgroup of the already extinct marsupials.
They only occur in Australia and America, but not in Europe. So you have a good chance of seeing a marsupial when traveling to the USA.
What marsupials are there in America?
Within North America there is only the possum, which is considered a marsupial and can possibly be seen. It is quite possible that it was spotted in Canada as well, because it has spread.
Many other species live in South America. And most of the marsupials are – as already suspected – in Australia.

Oppossum
What are marsupials anyway?
The most famous marsupial is certainly the kangaroo. Because it obviously carries its offspring with it and transports its young in its pouch. There are also koalas and wombats, which most people are sure to be familiar with. The opossum and the robbery are certainly less known. In total there are as many as 320 species of marsupials and thus an enormous number of animals that carry their offspring around in their pouches.
But if you want to see them you have to travel for a while and you won’t be able to avoid the plane.