It’s kind of confusing as “Continent” means different things to different people.
“Continental United States” for example usually refers not to Alaska or Hawaii
Well while Hawaii is definitely not in that equation, Alaska is most definitely part of the North American Plate, as is Canada, as is Greenland, as is part of China, as is Mexico.
if the plate decided to go for a ride, all those places are coming with it.
But in geo-political terms they are not considered the same.
And nature also has a tendancy to fuse plates for long periods of time
and then snap them apart into independant pieces again, right now, i believe the european plate and the asian plate are considered to be fused and not jostling about independently, but nature has a way of changing her mind about that and then they are separate again
The country of Australia, sits on a plate that shares its name, but the plate runs all the way to India, New Zealand is on that plate, as well as papua new guinea.
Country names may change, Even their shapes might change some, but what they are sitting on doesn’t.