The melody of I Believe In Father Christmas by Greg Lake runs 295 notes across 35 bars, 2:40 long in D at 116 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 Believe In Father Christmas chords and lyrics.