Some people read into the King James Version translation of Isaiah 45:7 that God "created evil." Actually, if you bother to read other more reliable translations like the NASB, NIV, ESV, or NLT, you will see that in context God is referring to natural evil such as disaster, calamity, bad times, bad or hard luck, and so forth. God cannot create moral evil for God is moral and good and holy and there is no evil motive or thought in Him. God is pure goodness. A parallel verse to interpret this is Amos 3:6 which says does disaster come to a city unless the LORD has caused it. Job also in v. 2:10 thank God for bad times as well as good times as being from God
To be clear, God did create the possibility of evil just like when He created rocks and stones, He made it possible for Cain to murder Abel with one. A gun manufacturer makes murder possible but is not culpable for what a gun owner does with the weapons they manufacture. Now, God gave us free will and that means we must have the option to be evil or to disobey God. God cannot give us free will and then prevent us from using it against Him. Free will necessitates the possibility of evil and hatred or we would be robots and puppets forced or coerced to obey and love God.
First, we must realize what evil is. It is not the opposite of good for then it would be equal to it and something that is existing in itself per se. Evil is the distortion, perversion, and twisting of good; a deviation from the good. It is a parasite and parasites need a host (goodness!). If there were no good, neither could there be evil. Examples then of evil are unrighteousness, lawlessness, injustice, and unfairness. You see that the objective good must exist first. That is why God cannot create evil: it is not a thing, but a lack of good and a parasite a vacuum that sucks in error and falsehood. Evil was once good just like Satan was once perfect in all his ways till evil was found in his heart. God didn't force or tempt Satan to do evil or to be evil; he managed this unprovoked by God and on his own initiative.
Goodness is something that can be infinite and perfect for God is good and perfect in all His ways. But evil cannot be absolute or perfect or infinite, because it is a parasite and deviation. The power of evil is that it masquerades and parades as good and deceives people. Like mixing enough error or heresy into truth to inoculate or immunize one from the real thing, like a false religion. Yes, pagan religions and false religions are not totally evil or completely wrong! They do have an element of truth and enough good to deceive! Satan then is in the counterfeit business trying even to deceive the elect with heresy and false doctrines of demons.
Now God has reasons to permit and allow evil: We see good in contrast to evil, we get the opportunity for good in the midst of evil, we praise God for turning short-term evil into long-term good, and it is a test of our faith and character (some get better, some bitter). Soli Deo Gloria!