As I previously posted, I am NOT a screenwriter, but as a "creative" I understand process.
In the numerous vids and blogs I have listened to recently a very substantial percentage of the writers and producers I have heard seem to follow the basics that
mlesemann outlined for you. It doesn't matter if you are adapting a story, writing to specific client requirements or writing from personal passion,
look for the core of the story. Understand it, embrace it, personalize it. Then just spew out your first draft. Some jump in and write a script, some make copious notes, some write an almost novel-like narrative. Don't worry about how good, bad, consistent or logical it is; this version is the most honest version of how you initially were inspired, felt and reacted to the project. Michelangelo was supposed to have said that the sculpture was already in the marble; all he did was chip away the unneeded bits. The first draft is your marble. You now need to chip away the unneeded bits.
Every screenwriter and producer I have heard so far then mentions rewrites - lots and lots of rewrites. Sometimes dozens of rewrites. Finally there will be a script that works for the producer, the director and (hopefully) the writer. But the script may need to be rewritten again to fit the budget or more directly address the target audience. And don't kid yourself, if you want to write for a living you need to remember that this is the entertainment business, and the entire point of a business is to make a profit, which means appealing to the largest audience possible.
The script will then be adapted/rewritten again through the director when it is shot. And then again during the post process.
So I don't see how perusing the initial draft of the script would help you, as the script goes through many, many changes before it finally hits the market.
The most confusing and yet most obvious thing is that, although all of these successful writers follow the basics, they have entirely unique methods/processes on their journey to the final draft of the script. Just because writer ZYX uses method 975 doesn't mean that
YOU have to use method 975. So you will have to choose the tools/methods/processes that fit your personality as you blaze your own way through the wilderness which is the search for a great script. One writer said that she thought about it for a long time, made copious notes, wrote bios on key characters, set up the character and plot/story arcs, index-carded it all, and, after all this is completed, started to write. Another writer said that he just dove headfirst into the script and let it evolve on its own. The rest seem to work somewhere between these extremes. One writer said that the story and characters dictated his approach to writing the script, i.e. doing a sports screenplay meant immersing himself in the sport, but when writing a mystery he had the ending (almost) set in stone and worked backwards from there.
The same applies to me when wearing my hat as a music engineer/producer. The songs are the stories. My job is to take the artists concept & passion and turn it into something to which the audience can relate and enjoy without draining the initial spirit and passion. When I do audio post I am not simply sticking sounds to the visuals, I spend a lot of time attempting to select or create sounds that enhance the characters, move the plot/story and inform the audience. The first versions of these songs or soundtracks often have little resemblance to what I started with. But the core (hopefully) holds true. That is the challenge for every artist; to make something that connects to the audience while holding true to the core passion that started it all. The artists that can do that are the ones that are successful.
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A number of posts have appeared while writing this. I feel, although you and others may disagree, that a screenplay that adapts a short story is no different than any other screenplay. The format will be the same. Perhaps that is where you should start. Get a grasp of the basics.
Again, my musical experience is relevant. Music is written on the page and can be read by any musician, whether it is an original piece or an adaptation. "Pictures At An Exhibition" (1874) by Russian composer Modest Mussorgsky (1839 - 1881) is a solo piano suite comprised of ten "reflections" based upon an exhibition of the art and architecture of Viktor Hartmann tied together by an evolving "Promenade" - Mussorgsky's walk through the gallery from picture to picture. "Pictures" was adapted by several composers, the most famous version by Maurice Ravel in 1922. Progressive rock group Emerson, Lake & Palmer (ELP) adapted some of the material from "Pictures" and rocked the hell out of it in 1971. Each adaptation is unique in and of itself, but the musical core remains the same.
Don't worry about how others have adapted stories; find your own voice. To beat you over the head with it, learn the basics - correct formatting, proper scene headings, relevant dialog and subtext.
Damn it Jay, can't you use Google? About 10 seconds gave me this:
How to Format a Screenplay (makeuseof.com)
Format has nothing to do with the content. Covers of songs follow the same basic format. The difference is only in the interpretation.
Mussorgsky - Pictures at an Exhibition (original piano version) - YouTube
Pictures at an Exhibition: Promenade (part 1) - YouTube
Promenade (Pt. 3) (Live At Newcastle City Hall, 1971) - YouTube
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Just for fun you may want to watch three films - "The Shop Around The Corner" (1940), "In The Good 'Ol Summertime" (1949), and "You've Got Mail" (199

. The core is the same, the interpretations are all different. Oh, by the way, "The Shop Around The Corner" was based upon the 1937 play "Parfumerie."
The infamous "It's A Wonderful Life" (1946) was based upon the short story "The Greatest Gift;" every publisher it was sent to passed it. So the author, Philip Van Doren, sent it out as a Christmas card, which is how it came to the attention of Frank Capra. For another oh-by-the-way "The Greatest Gift" was very loosely based upon "A Christmas Carol," probably the most adapted story in film history.
Well, there I go with another lock-down ramble. I wish you luck!