This puzzle confused me

lichess.org/training/RLUla

Can someone tell me why Qh6 is the move? Doesn't it hang the knight on e5? And why does black respond with Ne4? It doesn't really need to block that bishop since that knight is covering the mating square. What am i missing here?

EDIT: After looking at it for a while, i understand that if black took the hanging knight, then Nh5 checkmate is inevitable.

Queen is threatening mate on h7 and black tries to block with Ne4.

"Queen is threatening mate on h7"

Not initially because black has a knight on f6. The threat is Nh5, removing the defender of h7, followed by Qh7#.