The melody of 1 2 3 by Len Barry runs 155 notes across 27 bars, 2:07 long in C at 100 beats per minute. The tab sits almost entirely in the first two frets, one note at a time — no chords to barre and no strumming pattern to keep up with. A piano backing track plays the chords and bass underneath, so the line you are learning sounds like the record even at half speed.
Prefer to strum and sing it instead? 1 2 3 chords and lyrics.