"The mountain is good"?
Nope. That would be "Blēnon sȳrior issa."
What country is this language spoken in?
None. It's a made up language.
But could you get by with it in say, Switzerland, or in the big European cities that get a lot of tourists?
It's a fictional language. The only people who speak it are characters in Game of Thrones or fans of Game of Thrones. So the only possible real life places to use it are those where many Game of Thrones fans are, like fan conventions...
Or stupid people like me who want to learn this language for no reason