I see, that's why you asked "what boots?". You need the boots eventually, but first you need to beat the sneaky ghost.
So you can't go close it, what do you do? Attack it from a distance! You have a weapon (25 of it) that can help you do that.
The ghost is above the item, so it's about the same height when you jump halfway. So if he's on the top left platform, you go to the top RIGHT platform and jump + throw.