The babies would drown in the Nile and die.
It isn't known which Pharaoh it was.
To keep him from death. the pharaoh though there were too many Hebrews and decided to kill the new born male babies.
According to the Bible, Moses was a baby when he was placed in a basket on the Nile River to escape Pharaoh's orders. His exact age at the time is not specified in the scriptures.
Moses was rescued by the pharaoh's daughter when he was placed in the Nile River in a basket as a baby. She found him and raised him as her own.
The Pharaoh
Moses' mother placed him in an ark of bulrushes and set it adrift in the Nile River to protect him from Pharaoh's decree to kill Hebrew baby boys. Moses was later discovered by Pharaoh's daughter and raised in the Egyptian palace.
Exodus chapter 2 describes the birth and early life of Moses. Moses is placed in a basket and set adrift on the Nile River to save him from Pharaoh's decree to kill all Hebrew male babies. He is found by Pharaoh's daughter, raised in the royal court, and eventually flees to Midian after killing an Egyptian taskmaster.
His mother placed him in a waterproofed basket in the Nile river, and he was picked up by Pharaoh's daughter. See the details in Exodus ch.2. Also:Moses' biography
The Nile.
Cleopatra VII
the Pharaoh's daughter ( the pharaoh of Egypt) found baby Moses.
It was believed that the gods gave the pharaohs their powers to make the Nile flood for the farmers.