God spoke to Aaron, "Go and meet Moses in the wilderness." He went and met him at the mountain of God and kissed him. Moses told Aaron the message that God had sent him to speak and the wonders he had commanded him to do.
So Moses and Aaron proceeded to round up all the leaders of Israel. Aaron told them everything that God had told Moses and demonstrated the wonders before the people. And the people trusted and listened believingly that God was concerned with what was going on with the Israelites and knew all about their affliction. They bowed low and they worshiped.
Exodus 4:27-31

I have a few thoughts to share about Aaron, Moses older brother in the Bible.

I have focused on Moses, how he ran away and lived in the desert all those years, until the burning bush. Moses had been saved from the killing of all the babies and raised in the royal household, and later ran to Sanai. Aaron stayed in Egypt among his enslaved people.

When God calls Moses from the burning bush, which is the beginning of the central event of the OT, God also calls Aaron to help Moses. God already knows that the main guy needs help. God had set Moses aside for all these years, always having in mind this plan for him to be the leader with a capital L, yet God also knows that his man needs a right hand man and provides one in his older brother.

Aaron was right there with Moses during all the talks with Pharoh, the confrontations, the plagues. Together, they called out the people to leave.

You might be wondering how you could possibly do something, but God has your Aaron for you. Or, you might be an Aaron who is suffering with the suffering and God has an "out of left field" plan for you with someone or something you had given up on.