And indeed, for you in livestock is a lesson. We give you drink from that which is in their bellies, and for you in them are numerous benefits, and from them you eat.
Allah's Signs and Blessings in the Rain, Vegetation, Trees and Cattle
Allah mentions His innumerable blessings to His servants, whereby He sends down rain in due measure, meaning, according to what is needed, not so much that it damages the lands and buildings, and not so little to be insufficient for crops and fruits, but whatever is needed for irrigation, drinking and other benefits. If there is a land that needs a lot of water for its irrigation but its fertile soil would be carried away if rain fell on it, then Allah sends water to it from another land, as in the case of Egypt, which is said to be a barren land. Allah sends the water of the Nile to it, which brings red soil from Ethiopia when it rains there. The water brings the red soil which is used to irrigate the land of Egypt, and whatever of it is deposited is used for agriculture, because the land of Egypt is infertile, and most of it is sand. Glory be to the Subtle One, the All-Knowing, the Most Merciful, the Forgiving.
The reason why olive tree has been associated with the Tur mountain is that this tree first grew on that mountain. Some people have said that it was the first tree to grow on earth after the great Deluge in the days of Sayyidna Nuh (علیہ السلام) . (Mazhari)
Then there is a mention of the blessings and the numerous gifts which Allah has provided for the benefitof ankind so that they may ponder and worship Him. The words of the verse are وَإِنَّ لَكُمْ فِي الْأَنْعَامِ لَعِبْرَةً (And indeed there is a sure lesson in the cattle for you - 23:21). The lesson to which this verse refers has been described further in the words نُّسْقِيكُم مِّمَّا فِي بُطُونِهَا (We give you a drink from that which lies in their bellies - 23:21). Some of the ways in which the cattle serve mankind are that they provide milk which is a very clear and nourishing food; every part of their body is put to some use, and their wool, hides, intestines etc. are all utilized, in industries which support a country's economy, the meat of the animals, which are halal (permissible) is a favourite food for all men. وَمِنْهَا تَأْكُلُونَ (and of them you eat - 23:21). And finally they are used, together with ships, as mounts and as means of transporting goods from one place to another.
Tazkirul Quran
Maulana Wahiduddin KhanOn ayahs 16–21
The young one of a human being grows in the womb of his mother. In ancient times, the period from conception till child-birth was shrouded in mystery. It was only in the twentieth century that modern scientific developments made it possible to observe the development of a baby in the mother’s womb and obtain direct information about it. The vivid Quranic description of the various developmental stages of the formation and birth of human beings, is surprisingly identical with modern scientific findings. This provides a clear proof of the fact that the Quran is the Book of God. Had it not been so, such similarity between the findings of modern research and the statements of the Quran, revealed fourteen hundred years ago, would not have been possible. The development of the embryo in the mother’s womb shows that the Creator of this world is the most perfect Being. Our knowledge of the creation of man from the very beginning, is sufficient to make us believe that a second creation will take place and will occur in exactly the manner described by the prophets.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.