Only your own consciousness is fundamental, i.e. directly experienced. All others are deduced to exist, from clues. But your own consciousness's origin is not fundamental; that is also deduced from clues (i.e., "apparently stuff that exists once didn't").

But any model of our own consciousness that fails to encompass others' as similar is sterile. We are all found to have brains; and damage to brains, or even to the stuff that feeds brains, alters or snuffs out consciousness. Brains turn out to be made of nerve cells, that are like other cells but specialized for processing information. Stimulating an individual nerve cell can trigger a thought, memory or sensation, repeatably. QED, consciousness is a phenomenon of nerve cells processing information.

Anything else is woo.

How you would build a thing that is conscious is not known. But we have existence proof that it's possible, so the rest is a matter of engineering. Philosophers and deists can do whatever the hell they want, but will have nothing meaningful to contribute.

Roger Penrose says it's emergent because quantum mechanics is emergent. You can also find stuff by David Bohm saying something similar regarding Bohmian mechanics or de Broglie-Bohm theory.

Here is Hameroff and Penrose's paper on Orch OR: https://www.sciencedirect.com/science/article/pii/S157106451....

What specifically do you mean by fundamental? Not made out of other things?