Most linguists formally classify English as Germanic (West Germanic, alongside Frisian, Dutch and German, though one Norwegian linguist made a case for it being North Germanic), though some people refer to it as a Romance-Germanic creole. It is quantifiably true that, if you want to read Old English, knowing Icelandic will be more helpful than knowing modern English.
When I was a child, I spoke like a child. Now I am a man and I speak like the King of England!
English is three different languages in a trench coat. It’s all borrowed to some degree.
Most linguists formally classify English as Germanic (West Germanic, alongside Frisian, Dutch and German, though one Norwegian linguist made a case for it being North Germanic), though some people refer to it as a Romance-Germanic creole. It is quantifiably true that, if you want to read Old English, knowing Icelandic will be more helpful than knowing modern English.
Three languages?
Not sure what the third one is. You could make an honest argument for a number of languages to be number 3.