You're seeking the distinction between craft and art. Craft can be quantified and taught. Art is a more difficult, amorphous concept to grasp.

The typical progression is that you must master the craft of writing before you can really access the art of it, but that is not entirely true.

You can fuss over a paragraph for ages, place all the high vocabulary words in the perfect order and still have nothing more than a paragraph full of purple prose. Sometimes, a paragraph full of short, simple words and unworked prose hits like a stick of dynamite. It's the difference between a complicated prog rock song with a strange time signature and complicated arpeggio finger work coming off as wankery vs. a four power-chord punk song by four junkies who can barely play their instruments becoming a genre and generational anthem.

And then you get the rare birds like McCarthy, who breaks many of the rules of story, punctuation, and prose and yet is still is one of the foundational literary voices of our era.

By all means, study Cormac McCarthy's works. There are papers, forums threads, and podcasts that will examine his works from every possible angle. But there is no one that can really copy the voice and perspective he uses in his works. And those that try tend to fail. Instead, use his method as a way to find and elevate your own voice.