How do you think god comes into the equation? What do you think about split brain syndrome in which people demonstrate having multiple consciousnesses? If consciousness is based on a metaphysical property why can it be altered with chemicals and drugs? What do you think happens during a lobotomy?
I get that evidence based thinking is generally not compatible with religious postulates, but just throwing up your hands and saying consciousness comes from the gods is an incredibly weak position to hold.
Likely a prefrontal cortex, the administrative center of the brain and generally host to human consciousness. As well as a dedicated memory system with learning plasticity.
Humans have systems that mirror llms but llms are missing a few key components to be precise replicas of human brains, mostly because it's computationally expensive to consider and the goal is different.
Some specific things the brain has that llms don't directly account for are different neurochemicals (favoring a single floating value per neuron), synaptogenesis, neurogenesis, synapse fire travel duration and myelin, neural pruning, potassium and sodium channels, downstream effects, etc. We use math and gradient descent to somewhat mirror the brain's hebbian learning but do not perform precisely the same operations using the same systems.
In my opinion having a dedicated module for consciousness would bridge the gap, possibly while accounting for some of the missing characteristics. Consciousness is not an indescribable mystery, we have performed tons of experiments and received a whole lot of information on the topic.
As it stands llms are largely reasonable approximations of the language center of the brain but little more. It may honestly not take much to get what we consider consciousness humming in a system that includes an llm as a component.