RobH_en_tn/1ki/19/09.md

to a cave there

Here the word "there" refers to Mount Horeb. A cave is an opening in a mountainside that leads to a natural room or rooms underground.

the word of Yahweh came to him and said to him, "What

The idiom "The word of Yahweh came to," is used to introduce a special message from God. See how you translated this in 1 Kings 6:11. Alternate translation: "Yahweh gave a message to him. He said, 'What" or "Yahweh spoke this message to him: 'What" (See: rc://en/ta/man/translate/figs-idiom)

What are you doing here, Elijah?

Yahweh asks this question to rebuke Elijah and to remind him of his duty. Alternate translation: "This is not where you should be, Elijah." (See: rc://en/ta/man/translate/figs-rquestion)