This seems to be a contradiction. Are you saying God is of the "natural" and not "supernatural"? If God is supernatural, then of course, creation of the materials from which you are made and the processes by which you were physically formed came about through supernatural powers.
Do you think stars forming right now off in the universe are not created by God unless he added something supernatural?
I of course have a eternal soul that is spirit, as God is spirit.
But that is not and never should be the realm of science.
But my physical body and physical brain have no need of supernatural intervention for their formation and function. They are all understandable chemical reactions on a larger and more complex scale than what we see in the humble flatworm.
Do you think that stars need magic added in order to be created by God?
Do you really?