No, English and Dutch aren't the same. But they're in the same language family. They're both members of the Teutonic family of languages. So that means that they're related to each other, and also to German.
No, the words 'Italian' and 'Sicilian' don't mean the same in English. Neither do they mean the same thing in Italian or Sicilian. In Italian, the words are 'italiano' and 'siciliano'. The word...