This is very philosophical and not answerable here or anywhere. It’s also very personal. You could have ambition to change the world, help your fellow humans,

This is very philosophical and not answerable here or anywhere. It’s also very personal. You could have ambition to change the world, help your fellow humans, cure diseases, whatever. Those are noble. You could also view life as a journey of self discovery. In that case, having children can help discover your true self. Or is it your true self? How do you know? Or maybe children are God’s gift, and it’s your religious responsibility to have children so that they can experience God’s world. Or it’s a biological trick to ensure survival of the species. That is a scientific but unfulfilling answer. There is no right or wrong answer.