The word "nations" is a metonym for the people of the nations. Alternate translation: "The people from many nations" (See: [[rc://en/ta/man/translate/figs-metonymy]])
Here "his ways" and "his paths" refer to what God wants the people to do. "Walk" means they will obey what he says. (See: [[rc://en/ta/man/translate/figs-metaphor]])
The law and the word going out is a metaphor for people hearing it and then being messengers to tell other people about it in other places. Alternate translation: "people will listen to the law in Zion and go out and tell others; they will listen to the word of Yahweh in Jerusalem and go out and tell others" (See: [[rc://en/ta/man/translate/figs-metaphor]])
The words "will go out" are understood from the previous phrase. They can be repeated here. Alternate translation: "and the word of Yahweh will go out from Jerusalem" (See: [[rc://en/ta/man/translate/figs-ellipsis]])