“I AM WHO I AM” (Exod 3:14).
“God’s existence and character are determined by Himself alone and are not dependent on anyone or anything else.”
God does not need any part of creation in order to exist; but neither does He need any part of creation for any other reason. He is absolutely independent and self-sufficient.
Not only this, but God could not need the creation for anything.
“The God who made the world and all things in it, since He is Lord of heaven and earth, does not dwell in temples made with hands; nor is He served by human hands, as though He needed anything, since He Himself gives to all people life and breath and all things” (Acts 17:24-25).
All else that exists is entirely and constantly dependent on His existence.
(Spotlight 5, Lesson 2 in Doctrine 101: Learning about God)