After the children of Israel crossed safely over the Red Sea, they became hungry and thirsty at times, and they begged Moses to lead them back to Egypt where they had plenty to eat. They should have believed in Moses and God, that He would send them food. But they did not have patience, instead they grumbled. Moses prayed to God for them. Then God sent manna from heaven. Manna took the place of bread for them. God also gave them water to drink. Each morning they found the manna on the ground and at night God sent them quails to eat. God took wonderful care of the Israelites during their journey in the wilderness (desert).
God also wanted the Israelites to obey Him. God gave them some laws and the Ten Commandments. The Israelites said they would obey God.
Here are the Ten Commandments simplified: