Short answers, pulled from the story.
Ancient Egyptian creation myths are accounts of how the world came into existence, each associated with a particular god and city in Egypt. The main traditions originated in Hermopolis, Heliopolis, Memphis, and Thebes, and together they form the earliest recorded religious compilations in the world. All versions begin with primordial chaos, a state called Nu, from which the first mound of earth and the sun emerged.
The benben was a pyramid-shaped mound of earth that, according to Egyptian creation myths, was the first thing to rise out of the primeval waters of chaos. The imagery was likely inspired by the annual flooding of the Nile, whose receding waters left the highest mounds of fertile earth visible first. The sun was said to have risen from the benben at the beginning of creation.
Zp tpj, meaning "the first time," was the Egyptian term for the moment of creation. It denoted the transition from primordial chaos into the ordered world. The phrase captured the Egyptian understanding of creation as a moment of passage rather than an act of construction.
Atum was the creator god of the Heliopolitan tradition, closely associated with Ra. He was self-engendered and existed in the primeval waters of Nu before emerging onto the mound to begin creation. He produced the air god Shu and Tefnut, whose descendants formed the Ennead, the group of nine gods central to Heliopolitan cosmology.
In Memphite theology, Ptah created the world through thought and speech alone. Ideas formed within his heart, which the Egyptians regarded as the seat of thought, and when he named those ideas aloud with his tongue, the named things came into existence. Memphite theology also held that this intellectual act of creation caused Atum and the Ennead to form.
The Osiris myth linked creation to royal power by identifying the living pharaoh with Horus and the dead pharaoh with Osiris. Set's murder of Osiris and Horus's subsequent victory over Set provided a cosmic narrative that grounded Egyptian kingship in the structure of the universe itself. This is why the Pyramid Texts and tomb inscriptions from the Old Kingdom are the primary sources for these creation accounts.