How was the spirit of evil produced in humankind, knowing that God breathed into us of His spirit, and will this spirit be eternally tormented in the Fire?

The attribution of the soul to Allah Almighty in His saying: "and breathed into him of My spirit" is an attribution of honor and veneration. For the soul is a creation among Allah's creations, and not an inherent attribute of His essence. The soul, by itself, does not produce evil; rather, evil results from the combination of the soul and the body. The self becomes wicked or pious through their union. The soul enters the human body by Allah's command through the angel appointed over the wombs. And when a person chooses the path of evil and his soul becomes consumed by it, it becomes corrupt and is punished.