Either God created everything, or he didn’t.
Which is it?
Like I said. God created all the angels. Some rebelled and God threw them out of heaven.
But they were angels first.
I don't see the conflict. He did create everything. He created it and declared it "good". Lucifer mutated of his own free will. God didn't create him to do evil but he foresaw the possibility and planned for it. He is omnipotent and can foresee problems we cannot.
Yes. God created all of us. He gave us free will to follow him or to sin.
We make the choice to sin. Perhaps we are influnced by Satan, but we make the choice.
We need to blame ourselves and be thankful for God’s mercy and his graces.
God’s Peace be with you.