How did Confucius collect and sort out existing cultural classics at that time?

Confucius was a cultural celebrity living in the late Spring and Autumn Period. Confucius founded private schools in history. "Seventy people are proficient in six arts" (Historical Records Confucius Family). In order to compile teaching materials, Confucius collected and sorted out the existing cultural classics at that time, "deleting poetry books, setting rituals and music, revising the spring and autumn period and changing the order".