The intro progression is basically the entire song, with a small exception during 
the bridge when you drop the Em7

Listen to the song for precise timing.  It's easy.

Intro

Cadd9 Gadd9 D Em7 x2

V1

Cadd9  Gadd9
                    I could write a love song
D  Em7
             Tell You what I think You wanna hear
Cadd9  Gadd9                            D  Em7         
             But it wouldn't be good enough, no
Cadd9  Gadd9
              Yea I could try so hard
D  Em7
             To give it everything I've got
Cadd9  Gadd9                   D  Em7
But I'm not ever gonna measure up

[Chorus]

          Cadd9
All I can do is thank You
Gadd9          D             Em7
For this life I never deserved
            Cadd9                   Gadd9
Wanna thank You for the grace
               D                  Em7
I know I don't have to earn
Cadd9                 Gadd9
You love me, You love me
         D              Em7
Your mercy is proof
    Cadd9  Gadd9     D     Em7
All I can do is say thank You
All I can do is say thank You

(V2 same as V1)
It would have been easy
But I'm glad You never walked away
Cause Your love runs deep for me
And I see this beautiful world
And it brings tears in my eyes
And I think it's beautiful to be free

[Chorus]

(Thank You)
    Cadd9       Gadd9      D                    
For hope, for love, for all the ways You move
(You)
For everything You do
(You)
What else can I say but thank You
Thank You

I could write a love song
Tell You what I think You wanna hear
But it wouldn't be good enough

[Chorus]

All I can do, all I can do, all I can do
Is say thank You
All I can do, all I can do, all I can do
Is say thank You