Surah: 006 Al-Anaam
This is a late Makki Surah, and it’s named Al An’aam, the Cattle, as it mentions the livestock that was used by the Quraysh, the polytheists of Makkah, to associate partners with Allaah (SWT).
It is Allaah (SWT) Who Has created everything, heavens and the earth, all are a sign for those who want to take heed.
They continuously demanded miracles and angels from the Prophet ﷺ. Angels are sent when punishment has to be carried out, as was done for previous nations. And if the angel was sent as a prophet as they wanted, then he would still appear in the form of a human, so that would beat the purpose of their demand itself.
If the disbelievers were to touch a book that was sent by Allaah (SWT) from the heavens, yet they would allege it to be magic, which was their accusation against the Qur’an as they could not comprehend how an illiterate man like the Prophet ﷺ present a work as that.