This is a fun one. It comes through Persian and Arabic from the Sanskrit “naranga-s” - which describes the tree. But despite the Dutch adoption of the color, the place name “Orange” in titles like William of Orange is from the Latin name “Arausio”, which probably has Celtic origin.
Almost. They both share the same Proto-Indo-European root, which is reconstructed as *wi-ro.
Germanic, Italic, Celtic, and even Indo-Iranian languages all have commonality in PIE.