It is a great song by the way. The number in the () means how many times to stum down.
[ Tab from: https://www.guitartabs.cc/tabs/m/misc_traditional/danny_boy_crd.html ]
C(2) C7(2) F(4) C(2) Am(2)
O Danny Boy, the pipes, the pipes are calling. From Glen to glen, and down
Dm(2) G(2) C(2) C7(2) F(4)
the mountain side. The Summers gone, and all the roses falling. It's you,
C(2) D(1) G(1) C(2) G(2) C(2) F(2)
It's you, must go and I must bide. But come ye back, when summers in the
C(3) G(1) C(2) A7(2) Dsus(2)G(2) C(2)
meadow. Or when the valley's hushed and white with snow. It's I'll be here
F(2) C(4) C(3) D(1) G(1) C(2)
in sunshine or in shadow. O Danny boy, O danny boy, I love you so.
All other verses are the same as this one! Enjoy!