God created out of Himself. Only He knows how this can be done. We can't expect to be able to understand everything compared to an infinitely great God. Science can't answer these questions. What science can do is observe cause and effect relationships in the universe, the universe God brought into being.

Theism is true because since proves it to be true. Since nature can't start up from nothing, nor always have existed because you would have happened already having had an eternity to do so if infinite regress were true, therefore nature needs a cause outside of itself, outside of time and space, being uncreated whom we call God. A mind is needed to create a mind since God also has a mind.

Science proves the resurrection of Jesus since you can't find a naturalistic explanation to account for the eyewitness testimony of the Apostles in various group settings.

The universe would not exist without God having created it; nothing in the universe would exist therefore if God didn't create the big bang. Praise the Lord!