# the whole plain of the Jordan

This refers to the general region of the Jordan River.

# was well watered

"had much water"

# like the garden of Yahweh, like the land of Egypt

"like the garden of Yahweh or like the land of Egypt." These were two different places.

# This was before Yahweh destroyed Sodom and Gomorrah

This anticipates something that would happen later. It is important here because it explains why Lot settled in a region that later was not fertile.