My first act as the new god will be to cause the bonds of all of the carbon dioxide atoms above a certain percentage in the atmosphere to separate into carbon and o2.

Black powder will rain from the sky and coat the earth.

Then I will dematerialize a very select portion of the population. I'll leave it to your imagination to determine exactly who that is, but I will clarify that it will only be people above a particular socioeconomic cutoff.

Then I will cause all of the plastics on the planet that currently inhabit living creatures to break apart Slowly enough that their metabolisms will be able to process the chemicals, followed by all known non-beneficial viruses and bacteria, followed by the dissolution of all microplastics on the planet, followed by the dissolution of all toxic wastes on the planet, followed by all invasive species on the planet.

Finally, I will cause excess body fat to be eliminated from the population, arteriosclerosis and cancer to break apart into carbon and water and whatnot, scars to fall off of the body, and all skin will become taut and youthful.

I'll then repair every human body on the planet to its genetically optimal self.

I will take prayers as far as what to do after that.