Lesson
White to move. Main line: 1. c6 bxc6 2. bxc6 Kf7 3. c7 Ke6
1. c6 is the only winning move in the position. The pawn is offered so that whichever way Black captures, a second pawn runs through: bxc6 opens the b-file for the b-pawn, and refusing lets c7 arrive with tempo.
This is the pattern to recognize in every pawn ending: a majority is only worth something if it can create a passer, and the way to create one is often to give a pawn away rather than push them side by side.
Every alternative first move here draws. That is what makes it worth showing — the breakthrough is not the best of several plans, it is the plan.