Pharaoh enslaved the Israelites, limited their freedom and treated them very poorly. Many of them died due to the harsh work they were forced to do.
While the Israelites were enslaved, Moses was born as Gods plan to help the Israelites escape Egypt. Moses was born into a Hebrew family, but was put into a river by his mother for Pharaoh's daughter to find and raise him.
Maiden take this child and bathe and nurse him.
God appears to Moses as a burning bush to calls upon him to free his people from the horrors of Pharaoh's ruling.
But God, I am nobody. What if they do not believe me?
My people are suffering in Egypt, so I am going to free them. Moses you are the one I am going to send to free them and lead them out of Egypt.
God sent the 10 plagues to punish the Egyptians for not listening to Moses about freeing the Israelites.
Water turns to blood
Hail and fire
The 10th plague would kill all first born sons. To protect his peoples sons, God told them to sacrifice a lamb and spread its blood on their front doors.
Praise the Lord, our son shall live.
After the 10th plague killed Pharaoh's son, he changed his mind and let the Israelites leave Egypt.