The melody of I Don’t Know by Paul McCartney runs 253 notes across 55 bars, 4:23 long in Eb at 80 beats per minute. The tab sits low on the neck, mostly under the fourth fret, 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? I Don’t Know chords and lyrics.