Yes, it depends on the platform. For example, on some social media platforms, there may be notifications or analytics that show if a story has been shared with someone. Also, if the person you send it to mentions it to the original creator, then they would know.
Well, it depends on the app you're using for the story. For instance, Snapchat used to notify users when someone took a screenshot of their snaps (which are a type of story). But other apps may not have such a straightforward way. There are some third - party apps that claim to be able to track screenshotting, but they often violate the terms of service of the main apps and might not be reliable. So in general, it's hard to be certain if someone has screenshot your story.
It depends on the person's perception and understanding. Some people might have a good ability to grasp the details and essence of a story, while others might miss key points.
Yes, someone can see a stop story if they have access to it. Maybe through a website, a book, or if it's shared by someone who has it. But it also depends on if they are interested in looking for it.