Ancient Egypt is a very big topic. Broadly speaking, the history of Ancient Egypt is divided into Old Kingdom, Middle Kingdom, and New Kingdom. There are over 30 dynasties and 300 pharaohs. Important pharaohs for the Old Kingdom would be Menes (who is credited with unifying all of the cities up and down the Nile valley into one nation) and Cheops (also known as Khufu) would built the great pyramids. At the end of the Old Kingdom, Egyptian civil government decayed, there were rebellious nobles and a period of anarchy called the First Intermediate Period followed. This was ended when the ruler of the city of Thebes once again unified the Nile and began the period known as the Middle Kingdom. After several centuries, the Middle Kingdom pharaohs lost control again, at least partially due to attacks on the delta region by foreigners known as the Hyksos. The New Kingdom began when the rulers of the city of Thebes once again unified the valley. Important New Kingdom rulers are Ahmose (who drove out the Hyksos), Thutmose III (who led military expeditions that conquered Egypt's neighbors), Hatshepsut (the only woman to rule as Pharaoh).
Most intriguing ruler of the New Kingdom is Pharaoh Akhnaton, the heretic Pharoah, who founded a new religion devoted to the worship of the Aton or the sun disk. Ra had been the leading god in the Old Kingdom, and Amun, god of Thebes was worhipped in the Middle & New Kingdom. Akhnaton was a monotheist. His reforms did not survive his death. Egypt once again collapsed, then was overrun by the Assyrians, the Babylonians, briefly revived, then conquered by Alexander the Great, whose general Ptolemy and his descendants then ruled until Egypt was absorbed into the Roman Empire on the death of Cleopatra soon after the death of Julius Caesar.