The Azores are a part of Portugal. That means that, like the rest of Europe, the currency on the islands is the euro. As part of Portugal, the main language of the islands is Portuguese and it can definitely be helpful (especially in smaller towns) to know some common phrases in Portuguese. Azorean Portuguese is super similar to what’s spoken in mainland Europe - with the exception of the island of Sao Miguel where the accent is truly unique. That being said, English is widely spoken across the islands, so with some key phrases, a translator app on your phone, and some patience you should have zero issues enjoying your time in the Azores!