The question
The passage opens simply: And indeed, Ilyas was from among the messengers, when he said to his people, Will you not fear Allah? Do you call upon Ba'l and leave the best of creators — Allah, your Lord and the Lord of your first forefathers? (37:123-126).
That is his whole recorded message: one question, in two halves. Not a lecture, not a threat — a comparison. You have picked this. Look at what you put down in order to pick it up.
Ba'l was a named idol worshipped in the region. The Quran does not describe it or its rituals, and does not need to. The argument works whatever the statue was.
What happened next
The Quran is brief: And they denied him, so indeed, they will be brought — except the chosen servants of Allah (37:127-128).
Then, unusually, four verses of peace and praise: And We left for him favourable mention among later generations: Peace upon Ilyas. Indeed, We thus reward the doers of good. Indeed, he was of Our believing servants (37:129-132).
There is no account of what he did afterwards, how long he stayed, or how it ended for him. The Quran gives the question, the refusal, and then greets him by name.
Why the short ones matter
By this point in a run of prophet stories, a child has met several who were sent, refused, and then vindicated. Ilyas is a compressed version of the whole pattern in ten verses.
It is a good moment to ask a child what they notice repeating. They will usually get there: the prophet is one person, the people say no, the Quran ends by naming him with honour anyway. Recognising that shape themselves is worth more than being told it.