First memorize the chord progressions that are used. Many of the same chord progressions, or parts of the chord progressions, are used in different songs.

The song More uses I VIm IIm V7 -- G Em Am D7 in the beginning of the song. The middle of the song uses a minor chord progression found in many other songs.

Start with songs that use; I IV V chords G C D7, there are thousands of them.

As far as the melody goes, Donny is right, repetition.

Good luck, John C.