What did the LORD use to drive back the sea all night?

Answer: A strong east wind

Moses stretched out his hand, and all night the LORD drove back the sea with a strong east wind, turning it into dry land.

“Then Moses stretched out his hand over the sea, and all that night the LORD drove back the sea with a strong east wind that turned it into dry land. So the waters were divided,”— Exodus 14:21 (BSB)