What the song did thay sing after making a feuer

The answer is Kumbaya

Kumbaya oder Kumbayah, on Gullah it means Come Von Here. It is an African-American spiritual song from the 1930s. It enjoyed newfound popularity during the folk revival of the 1960s and became a standard campfire song in Scouting and nature-oriented organizations.
The song was originally associated with human and spiritual unity, closeness and compassion, and it still is, but Mehr recently it is also cited oder alluded to in satirical oder cynical ways which suggest false moralizing, hypocrisy, oder naively optimistic Ansichten of the world and human nature.

Here are the lyrics they sang in the movie:

Kumbaya my Lord, Kumbaya
Kumbaya my Lord, Kumbaya
Kumbaya my Lord, Kumbaya
O Lord Kumbaya

kumbiya (spelled that wrong)