It can be made explicit that their goal was to get him drunk. AT: "drink wine until he gets drunk" or "get drunk with wine" (See: [[rc://en/ta/man/translate/figs-explicit]])
This speaks about giving Lot descendants as if his family were a line that they are making longer. AT: "so that we can bear children who will be our father's descendants" (See: [[rc://en/ta/man/translate/figs-metaphor]])