Short answers, pulled from the story.
Scholars date the final form of Genesis to after the Babylonian Exile, possibly in the fifth century BCE. This conclusion contradicts ancient traditions that credit Moses as the author of the entire Torah.
The documentary hypothesis suggests four distinct sources: the Yahwist, the Elohist, the Deuteronomist, and the Priestly source. Each source used different names for God, such as Yahweh or Elohim.
In the Garden of Eden, a serpent convinces Eve to eat fruit from the tree of knowledge before Adam joins her. They hide their nakedness before God exiles them from the garden.
Four major groups of surviving manuscripts preserve the text today including the Masoretic Text, the Samaritan Pentateuch, the Septuagint, and fragments found among the Dead Sea Scrolls. The original manuscripts are lost leaving modern readers with these varied copies.
Religious authorities calculated the age of the world using genealogies in Genesis through an Anno Mundi system that forms the basis of the Hebrew calendar and Byzantine calendar. Counts generally place Earth's age at about six thousand years.