Do flies, mosquitoes, and insects have souls and lives like humans, and what is the difference between their souls and the souls of humans and other animals?

Animals and insects are nations like us; it is not permissible to harm or kill them except for what the Sharīʿah has permitted to be killed, and they should be killed in the best manner. As for their souls, that is a matter of the unseen, the essence of which is known only to Allah the Almighty, as He says: "And they ask you, [O Muhammad], concerning the soul. Say, 'The soul is of the affair of my Lord. And mankind has not been given of knowledge except a little.'" The difference between them and humans is clear; humans are honored with intellect and charged with worshipping Allah alone.