Are you people even in the US? J/k
1st floor, 2nd floor, 3rd floor.
Lol
It varies by your region/country, yes, but also where you actually grew up. People that grew up in NYC and high rises will colloquially use different language when describing floors than those who grew up on farmland with a 2 floor ranch house.
Personally, I wouldnt, nor anyone I know, call that house anything but 1st floor/2nd/3rd. We'd never use the term "ground floor". Like I said, the only time I've ever come across the term being used is in multi-level office buildings and such--never when describing a single residential home.