Paul Scraton has the following recommendations:
In his essay on the history of the short story, William Boyd argues that the short story is more natural to us than the longer form. After all, we are used to telling each other stories over dinner or on the bus – something funny that happened at school or a moment of injustice witnessed on the street corner. This is how we communicate with our friends and our families on a daily basis, and each time we tell someone else the same story, we make slight changes and adjustments in order to tell it better… which is all to say: we all tell stories all the time, so don’t be intimidated by the idea of writing one down, and editing will almost always make your story better.
William Boyd: https://williamboyd.co.uk/a-short-history-of-the-short-story/
The Guardian in 2021 published a nice article on how to write a great short story which is well worth a look but in general the best writing resources can be found in the work of other writers. There are so many great short story writers that it is hard to know where to begin, but Literary Hub put together a selection of top short story writers as recommended by other writers, that might be a good place to start.
Literary Hub:
https://lithub.com/17-great-writers-and-their-favorite-story-collections/
Swiss Creative Writing Prize 