First, kudos to the ancient Hebrews for several things:

For composing some tittilating myths and evolving these from generation to generation, campfire to campire,

For inventing a written language,

For using it,

And for conserving their papers for so many subsequent centuries.

Now, on to the question at hand:  To believe that God is all good, that Satan is bad, and that God created everything, is implausible.  Impossible, in other words.  They can NOT be true all three.

(I shouldn't be sharing my secrets for free.)

The Judeo-Christian gist is that God created Lucifer, a marvelous angel, and that this Lucifer rebelled and so became Satan, source and impetus of Evil (the opposite of good, the virtual opposite of God).  This is well and acceptable as myths go unless one believes both this myth AND that God is all good, that Satan and not God is the origin of "evil", "bad", "not good", etc.

If the myth is true then this, too, is true:  When God created Lucifer God created in Lucifer the potential for evil.  Were this not so then Lucifer could not have rebelled, could not have become evil.

Let me say it another way:  If God created Lucifer and Lucifer became evil, then God HAD to, when "He" created Lucifer, create within this Lucifer the potential to become evil.  In other words, God, and not Lucifer (Satan) is the origin of evil.

God had to create the concept of evil (and what is evil if not a concept?) when God created Lucifer.  Otherwise there would have been no potential for Lucifer to express evil.

You can believe that God created Lucifer and that this Lucifer became evil ONLY if you accept that God (and not Satan) is the origin and impetus of evil.