adding to this very good answer: especially in Europe legal, cultural and language borders can differ quite a bit due to history and geography. I’m from South Tyrol, an italian province at the Austrian border. The majority of people there speak a german dialect, we have german schools, public administration and everything, but are a language minority in Italy. The historic explanation is that after WW1 this region became part of Italy, taken fron Austria-Hungary.

Further there is a third official language in South Tyrol, basically only spoken in two valleys anymore, the “Ladin”. It’s a very old language, related to similar language island in adjacent italian provinces and Switzerland. Those languages basically just preserved themselves for geographic reasons (hard accessible valleys and mountains). for this reason those languages tend to differ already between to neighbouring valleys. I was tought, that most of South Tyrol spoke Ladin at some point, but after the Swiss turned Calvinistic, the catholic (and austrian) bishop of the region forced the south-tyroleans to speak german to distance them from the heretic Swiss.^^

During WW2 the fascists in Italy forced South Tyrol to speak italian and forbade everything german, including local, personal and family names; one reson certainly was to enforce this ideology of “one nation, one culture, one people”.

Returning to OPs question: In South Tyrol there are german schools, where you learn italian and english as mandatory second languages, analogously for italian schools. Both languages are valid for any official entity (in theory). In the valleys mentiined above, they also have ladin schools.