You know he's basically just adding melody notes into alternate chords and it can be done many different ways. Though his is very beautiful
In case you don't have it. Here are the chords and lyrics to the song
You can practice it with just strumming to familiarize yourself with the chords.
“A Thousand Years”
(Bb) (Gm) (Eb) (Bb) (F)
(Eb)Heart beats fast
Colors and(Bb)promises
How to be(Gm)brave?
How can I(Cm)love when(0330) I'm a(Eb)fraid to fall?
But watching you(Bb)stand alone,
All of my(Gm)doubt suddenly(Cm)goes a(0330) way some(Eb)how.
(333) One(3330) step(Eb)clo(F)ser
[Chorus:]
(Bb)I have died everyday waiting for you
(Gm)Darling, don't be afraid I have loved you
For a(Eb)thousand years
I'll love you for a(Cm)thousand(F)more
(Eb)Time stands still
Beauty in(Bb)all she is
I will be (Gm)brave
I will not (Cm) let any (0330) thing (Eb)take away
What's standing in (Bb)front of me
Every (Gm)breath
Every (Cm)hour has(0330) come to(Eb) this
(333) One(3330) step(Eb)clo(F)ser
[Chorus:]
I(Bb)I have died everyday waiting for you
(Gm)Darling, don't be afraid I have loved you
For a(Eb)thousand years
I'll love you for a(Cm)thousand(F)more
And(Bb)all along I believed I would find you
(Gm)Time has brought your heart to me I have loved you
For a(Eb)thousand years
I'll love you for a(Cm)thousand(F)more….
(333) One(0330) step(Eb)clo(F)ser
(333) One(3330) step(Eb)clo(F+C)ser
[Chorus:]
I(Bb)I have died everyday waiting for you
(Gm)Darling, don't be afraid I have loved you
For a(Eb)thousand years
I'll love you for a(Cm)thousand(F)more
And(Bb)all along I believed I would find you
(Gm)Time has brought your heart to me I have loved you
For a(Eb)thousand years
I'll love you for a(Cm)thousand(F)more….