Everything you need to learn the song is here. The pdf of the score can be downloaded below. Listen first to the tutti version of the song which has all voices equal in volume. If you want some extra help (especially basses and sopranos), listen to the one specially marked with your usual vocal range. The “tenors” are singing the main tune, which is also the simplest.
This song features the poem by Crowfoot (also known as a Blackfoot warrior chief and peacemaker of the Siksika nation (east of what we know as Calgary), who lived from 1830 to 1890. His poem goes like this:
What is life? It is the flash of a firefly in the night. It is the breath of a buffalo in the wintertime. It is the little shadow which runs across the grass and loses itself in the sunset.