Leviticus 16:15, 21

“Then Aaron must slaughter the first goat as a sin offering for the people and carry its blood behind the inner curtain. There he will sprinkle the goat’s blood over the atonement cover and in front of it, just as he did with the bull’s blood.

He will lay both of his hands on the goat’s head and confess over it all the wickedness, rebellion, and sins of the people of Israel. In this way, he will transfer the people’s sins to the head of the goat. Then a man specially chosen for the task will drive the goat into the wilderness.