In the beginning, before time and space existed, there was God, "In the beginning, God created the heavens and the earth" (Genesis 1:1). Everything that exists was created by Him, for Him, and through Him (Colossians 1:16). The universe, with its trillions of galaxies and stars, is just a small part of God's infinite existence. His rule and reign transcend infinitely beyond the created realm.
God decided to create a planet in the center of a solar system in the middle of this universe and fill it with all kinds of living creatures. But He had a special plan for this planet. He created a species of being that was like Him and gave them rule and reign over the planet and realm. As Jesus said, "Is it not written in your Law, 'I have said you are "gods"'?" (John 10:34).