Moses asked God to appoint a leader so that the LORD's congregation would not be like what?

Answer: Sheep without a shepherd

Moses prayed for a man to lead Israel out and bring them in, "so that the congregation of the LORD will not be like sheep without a shepherd."

““May the LORD, the God of the spirits of all flesh, appoint a man over the congregation who will go out and come in before them, and who will lead them out and bring them in, so that the congregation of the LORD will not be like sheep without a shepherd.””— Numbers 27:16-17 (BSB)