A passed pawn, one with no enemy pawn in front of it or on an adjacent file able to stop it, only has one real obstacle left: the enemy king. If that king is too far away to catch up, the pawn simply walks to promotion and nothing can be done about it.
A quick way to check this is the "square of the pawn": picture a square drawn from the pawn to its promotion square, the same width as that distance. If the defending king is outside that square, and it isn't their move to step in, the pawn queens by force. Don't overthink a position like that, just push.
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White's pawn is miles from being caught, the black king is all the way on h8.
What is White's simplest winning plan here?
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