It's been written before that there's only 7 types of stories in the world, in the history of human kind, EVER.
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Overcoming the Monster: MC sets out to defeat their enemy.
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Rags to Riches: MC gains something they didn't have before, to then lose it, and gain it again.
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The Quest: MC sets out to an undiscovered location facing many obstacles and tempations.
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Voyage and Return: MC goes on a journey overcoming threats, returning with nothing but experience. Very similar to #3 but the difference is that in #3 MC gains something material at the end, whereas in #4 MC gains knowledge and experiences (immaterial things).
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Comedy: Light and cheerful, ends in a happy ending, more than humorous usually having a plot where conflict is created through poor lines of communication and then made clear with a simple explanation, like most romances.
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Tragedy: MC has a major character flaw that is ultimately their undoing (think of Batman).
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Rebirth: A certain event makes MC change their views on the world, making them a better person.
These seven types can then be further cataloged under the "Man vs" system
Man vs Man: MC fights against a certain human, or same species, individual (Harry Potter).
Man vs Self: MC struggles with their own self (Evangelion).
Man vs Technology: MC's main antagonist is of a technological aspect, anything from AI to a really hard to open jar (The Matrix).
Man vs Nature: Nature becomes the antagonist (Castaway).
Man vs Society: MC usually lives in a society where they are oppressed and sets out to change things (The Hunger Games).
Then you can further break that down to genres, and each genre will handle each story differently, but when you break them down they are all the same.
So you see, storytelling does not have THAT much diversity. Many authors have tried to break away from these basic plots, and guess what? Their stories sucked, hahaha! I'm trying to find an example, when I do I'll edit this and post it here.
I wouldn't worry too much about thinking "is my story original?" I would concentrate more in "is my story good?" It all comes down on how you spin your plot and what you can bring to the table. For example, my comics are FAR from original, everyone's seen the male MC with fire powers, or the vampire lovers, right? But it's about how you DEVELOP your story in an original way, THAT is where distinction lies! If you start using tropes that have been seen before that's when the story fails and becomes a cliche.