“je pense, donc je suis“ - René Descartes, Discourse on the Method
“Cogito, ergo sum” - Latin
“I think, therefore I am” - English
What Descartes was not saying, was I think therefore I have a body. Nor, I think therefore I have a brain. What he was saying was I think therefore I am conscious and consciousness is a property of the immaterial mind, not the physical processor the brain or physical housing of the body.
Thinking, yes, is processed by humans in the brain and disciphered by it. It is stored and retrieved by the brain and in many ways our person is limited by the genetics and biology of our minds, including our physiology which is impacted by other aspects such as gender.
The highest most powerful coding (software) is limited by its processor and by the housing of the processor, the computer tower which allows it to function optimally, such as having a fan to cool it out, unrelated to the coding but necessary nonetheless. The best coding in the slowest computer or processor is hindered tremendously.
And right now I am reading your posting and I assume therefore, you are. But I’m not thinking of you, as in your body, nor your brain the organ, I am thinking that you the person, the intelligence exists and I am interacting with you the mind (and spirit/life).
If I read any material that contains autobiographical markings I can infer that at the very least, that mind existed. A biolographical marking I can infer another mind influenced the mind that write the biography, therefore at least two minds/persons.
In much the same way God has left written text, and from the text we can infer that this mind/person at the very least existed. Further based on what God prophecied and also came to fulfillment, God was able to know or predict at least, future events sometimes centuries in advance.
There is the issue of God’s disembodiment but I would refer you to my response in a separate question as to the fact that God overcame this issue.
Is God's disembodiment problematic?