en_tn/1ch/11/18.md

three mighty men

"3 mighty men" (See: rc://en/ta/man/translate/translate-numbers)

broke through the army of the Philistines

"fought their way through the army of the Philistines"

the well of Bethlehem, the well at the gate

These two phrases refer to the same well. The second specifies which well in Bethlehem. See how you translated a similar phrase in 1 Chronicles 11:17. (See: rc://en/ta/man/translate/figs-doublet)

he poured it out to Yahweh

This means that he poured out the water as an offering to Yahweh. (See: rc://en/ta/man/translate/figs-explicit)