Again backwards. Children lack an understanding of evolution much like you lack one.
Man is also part of the animal kingdom. We are just a specific type of animal that evolved into higher intelligence than other animals. If you could peer into the ancient past you would see how life on earth evolved. You would see apes are literally our distant cousins. As are frogs and chickens and every other animal. As are even plants and bacteria if we go far back enough in time. At some point of the past we shared common ancestors with other life on this planet. Brother and sister. One zigged while the other zagged into new species..
Before there was life on earth there was natural elements and chemicals. These combined through random processes until the first cellular level life came into existence. Everything evolved from there.
If you want to go further back, where did the earth come from, where did sun come from.. there are answers for that too. If you keep going and ask where everything came from, even the alleged big bang, and whatever caused that, and whatever caused that, and so on…
Aristotle recognized this infinite recursion of causes problem with his prime mover. It has been discussed over and over again by scientists and philosophers throughout recorded history. Religionists just gave up and decided to insert the arbitrary concept god(s) to explain it. They could have equally claimed it was a super intelligence potato. Or fish named Fred. There is exactly the same amount of of evidence to support any claim… zero.
The real answer… we are limited by our science, the scope of our technology and the limits of our brains We don’t know and probably never will.