There was a time when the created universe was not.
If ever there was a time when there was nothing, there would be nothing now. Nothing comes from nothing. Therefore God was before the beginning.
There is no “might be” or “could have been” in God’s being. He is, always has been, and always will be.
There was a time when I was not. There was a time when the universe was not. There never was a time when God was not.
In Him we live and move and have our being.