en_tn/gen/13/09.md

Is not the whole land before you?

This rhetorical question can be translated as a positive statement. AT: "The whole land is available for you to use." (See: rc://en/ta/man/translate/figs-rquestion)

Go ahead and separate yourself from me

Abraham was speaking kindly to Lot and encouraging him to do something that would help them both. "Let's separate."

If you go to the left, then I will go to the right

Possible meanings are 1) "If you go one way, then I will go the other" or 2) "If you go to the north, I will go to the south." Abram let Lot choose the part of the land he wanted, and Abram would take what remained.