#before they lay down

before the people in Lot's house lay down to go to sleep

#the men of the city, the men of Sodom

"the men of the city, that is, the men of Sodom" or just "the men of the city of Sodom"

#the house

"Lot's house"

#both young and old

This means "men of all ages" and refers to the men of Sodom who were surrounding Lot's house. AT: "from the youngest to the oldest."

#that came in to you

"that went into your house"

#sleep with them

Your language may have a way of saying this politely. Some older versions say "know them." (See: [[:en:ta:vol2:translate:figs_euphemism]])