These phrases refer to any cities that sent out large numbers of soldiers. Alternate translation: "Cities that went out with a thousand ... cities that went out with a hundred" (See: [[rc://en/ta/man/jit/figs-genericnoun]])
"The city that went out" represents the soldiers of that city going out. It can be stated clearly why they went out. Alternate translation: "The city out of which a thousand soldiers went to fight" or "The city that sent out a thousand soldiers to fight" (See: [[rc://en/ta/man/jit/figs-explicit]])
"will have a hundred soldiers who have not been killed" or "will have only a hundred soldiers still alive." Here "remaining" refers to not being killed by the enemy.
# for the house of Israel
Possible meanings are 1) "to defend the house of Israel" or 2) "belonging to the house of Israel"
The word "house" is a metonym for the family that lives in the house. In this case it refers to Israel's descendants. See how you translated this in [Amos 5:1](./01.md). Alternate translation: "you people of Israel" or "you Israelite people group" (See: [[rc://en/ta/man/jit/figs-metonymy]])