Too political a question to be answered succinctly
Officially Catalonia is an autonomous region within Spain (even if there is a small bit of Catalonia in France since 1640).
Catalonia (capital Barcelona) has an own language, which is official (Spanish is also official in Catalonia), Government, Parliament, police, health service, a different culture, identity etc.
But yes, we are a country and maybe some day we will be an independent nation, of course in a peaceful way and if most of the citizens of Catalonia have voted "yes" in a referendum.
Scotland or Quebec are similar cases (nations which are not independent).
Catalonia is part of Spain. This is like asking if New York is a country. There are a couple separatists idiots just like you find in Texas in the United States. 99% of Catalans feel as Spanish as people from other regions. From Dali the famous artist to Pau Gasol, true Catalans love Spain. Of course there are haters, 1 or 2, these people are usually mixed and not true catalans.
No, Catalonia is not a 'country'. But Catalans are a 'nation'.
P.s. Catalonia is not just in Spain. There is also French Catalonia.
It's a REGION in Spain.
Spain is the country.
Regiones are akin to states in the US and Mexico, cantons in Switzerland, Provinces in many countries.
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i saw a lipdub for the independence of Catalonia. I looked it up and nowhere does it say Catalonia is a real country.