It’s definitely not a built-in Instagram feature, so when people talk about viewing stories quietly, they usually mean external tools. The idea is pretty simple: a service acts as a middle layer between you and the story, so you never appear in the viewer stats. One example you’ll run into pretty often is
https://privatestoryviewer.com/ , which basically loads the story for you in real time and doesn’t leave any trace on the original profile. It doesn’t notify the owner, and it doesn’t generate analytics on their end. The important part is choosing a viewer that doesn’t ask you to log in with your account — that’s the biggest red flag. If the tool works without credentials, it’s generally safer and keeps your own profile out of the equation.