I can’t explain to you how a whole brain works, but if the question was genuine, I would actually recommend starting with Blumenfeld’s “Neuroanatomy through Clinical Cases” textbook. It’ll demystify a lot of the larger scale questions around structure and organization. It’s fairly easy to study how neurons, axons and synapses work using any number of freely available resources. You’ll never find out exactly how every cell is wired, but after a while (especially if you have a comp-sci, ML or statistics background) you’ll realize that that’s besides the point.

I'm just curious as to when exactly quality arises from quantity

What do you mean? Are you referring to emergence?

The issue is that we know very very well that “consciousness” is not “one thing”, but rather a collection of features, all (or most) of which can exist in isolation, and all of which can have a whole spectrum of both pathological and “normal” forms or states.

Generally speaking, different features emerge at different scales, so there is no particular reason to think that all of the things that make up “consciousness” would emerge at the same scale, at the same level of organization, or even at the same physical location in the brain. We can assume that interesting features emerge at the “group of neurons” level or at the tissue level, but that’s a pretty wide scale.

Crude illustration: “consciousness” is much more like a network of microservices than it is a monolith… And it has fuzzy borders and is not even well encapsulated from its environment.

I'm referring to subjective experience. Which neurons have to fire for me to experience the subjective taste of chocolate? And how many neurons do I need before that can happen?

Blumenfeld won’t answer exactly that specific question, but it will help you understand how that works more generally.

The book covers how quality (subjective experience) arises from quantity (# of neurons)? Could you point me to a section please? I'm super intrigued.

The book as a whole gives you the tools to understand how emergence happens in the brain. I can point you to the resource, but I can’t do the learning for you.

It’s also possible you’re less interested in the brain per se, and more interested in “emergence” in the abstract. If that’s the case, there is no shortage of good books and resources you can turn to.

Look up “emergence science” and “complexity science” and go from there: it’s not an easy topic, it’s very cross-disciplinary, and to really understand it requires a fair amount of maths (imo).

Sure, give me the complete wavefunction of your body and fifteen trillion years to simulate it.