A few years ago, one of my daughters took a couple of courses in screenwriting at a university in California in very close proximity to Hollywood. When she came home, she brought her books with her, and I borrowed them for awhile. Sitting in a stack by my chair, they tantalized me for months, while I toyed with the idea of taking a plot that had been running through my mind for a novel and converting it to fit the silver screen. Format is apparently all-important. Certain words have to be used in certain ways.
Some words have to be capitalized and centered on the page.
Others have to be in parentheses. Formatting, however, is not writing, as I learned when I sat down with the format clear in my head but with the plot lying there as so much fuzz and buzz in the neurons. I was great at the format, but the plot and the dialogue and the words of the actual setting and action were lousy. So, about halfway through the project, I abandoned it altogether and started over, putting my ideas down in the form of a novel. It turned out lousy, too, but at least as I wrote it I didn t have to follow a scripted format.