Type a username and see what a public account posted in the last 24 hours. No login, nothing installed.
A story is a post that disappears after 24 hours. Inside the app you cannot open one without an account, and the author sees a list of everyone who watched. A viewer sits in between: it asks Instagram for the public stories of an account and shows them as plain files. You are not signed in anywhere, so your name has nothing to appear next to. What it cannot do is reach a closed account — if the profile is private, its stories are private too, and no service can change that.
You do not need a direct link to a story. The account name is all it takes.
You are not logged in, so you do not show up in the viewers list and nothing is liked or followed on your behalf.
If the account posted nothing in the last day, there is simply nothing to show. That is not an error.