I’m not going to argue with Stephen King, but one’s approach to writing a story is an individually determined process that only you can find. I expect everyone develops their own methodology, and from my experience, it takes trial and error.
King famously eschewed using an outline, even ridiculed it, yet many successful writers do. Some writers won’t start a story until they know how it ends, which is something else that King openly derided. I both agree and disagree with him. I do a broad outline but I rarely know how it ends. As I’ve said before, I need a plot point to aim at, even if I don’t know what’s beyond that plot point, and when I get there, I need another one, so even the so-called outline – I call it a map – can be an organic process.
In answer to the second part of the question, I always start with a premise that includes a protagonist, a world and at least one plot point. The protagonist always comes to me first, but this is not necessarily the case for other writers. I know their gender, age-range and something of their persona: are they a loner, or someone’s partner? Do they have special skills? What’s their role in their world? It’s just as important that I don’t know too much, as I prefer to learn about them as the story unfolds, just like the reader does.
The world is often genre-dependent: is it fantasy? Is it sci-fi? Is it crime fiction? Is it espionage? Is it past or future or contemporary? I need at least one plot point for the end of the set-up, which is tied to the premise. The premise is best understood by asking the question: what’s this story about? If you can’t answer that, I don’t think you can start.
The ‘blank page’ these days is more likely to be a blank screen. But I don’t start there, which again is a personal preference. I start with a notebook where I write what I call ‘sketches’, which could be backstory, but usually what-ifs. After a while, dialogue starts to come unbidden and that’s when the characters come alive. Until I get to that point, I know it’s not worth the effort.
The blank screen is my ‘canvas’ and I find that there’s a change in my thinking, which I can’t explain, but I mentally enter the story. So, on that point, I agree with Stephen King that ‘You must not come lightly to the blank screen’.