Can someone explain this puzzle?

https://chesspuzzle.net/Solution/202990

Nf5 is forking a queen and a rook at the same time. And if the queen goes away, it is also threatining checkamte, while queen is under attack and opponent is close to checkmate,blacks should try to exchange queens and be down by "just" a rook, there is even the idea by pushing pawn to e7 and blocking a queen from defense. I hope it helps

I think you've misread the position. After white wins back the exchange, white is only up a pawn, and black can win the e-pawn back. The position is materially equal, white is slightly better. The actual game was a draw. It is curious that the puzzle is "White to win", I really can't see how.

You are right but we should probably consider that on the kingside are two pawns for white and only one for black, and pawn vs one on the queenside, after rook takes pawn on e7, rook takes rook and It can still be winning for white. I think the idea is to centralized white king and then just there is idea about breaking though with two pawn and if black king is going to defend king side, white can attack on queenside. Would not black be overhelmed? But these are just ideas, so what do you think?

Well... I tried to analyse it with stockfish and with right play white wins. 

The pawn endgame is won for white.

In the game white didn't go for this, that's why it was a draw.

But indeed, this is the point : after Nf5, white recovers exchange, and if black takes e7 (what else), simplifications lead to "basic" won pawn endgame.

Here some analysis to demonstrate why the pawn endgame is winning for white :

Thank you for your analysis