So then please tell us, “Where did Satan come from?”
God created him, just as, if you are a Bible believer, He created mankind. Mankind is just a step lower than the angels in the scheme of things.
He, as in Satan, is an angel. To be more accurate, a fallen angel. He took 1/3 of the angels with him when he left Heaven. Any of this sound familiar?
Jesus mentioned seeing Satan fall from Heaven.