Please help me with this position.

Im currently reading Understanding Chess Endgames by John Nunn. I got to this position and the author just says that white is winning. I inputted the position into an engine and it says -6, but the comp cant win when im defending with the black side. The comp just keeps on checking me until its the 50 move rule and shows 0.00. I don't know how white can win this, it seems to me that the king is too far away.

This is a theoretically drawn position regardless of what the book says. The king is indeed too far.

It's a draw. John Nunn's endgame books are highly regarded; are you sure you didn't misread the part that you are referencing?

Oh yes sorry, the blacks king is on b3, I was reading the book without a board. Of course it's a simple win just qa1