Reposting an Instagram story is easy. Open the Instagram app, go to the story you want to share. Usually, there'll be a paper airplane-like icon or something that says 'Repost'. Click on it and it'll do the job for you. Just keep in mind that not all stories can be reposted depending on the settings of the original poster.
To repost an IG story, first, make sure the account owner has enabled the repost feature. Then, when you view the story, you should see a repost icon or option. Tap on it and you might be able to add a comment before sharing.
It's simple. Just find the story you want to repost, look for the 'Share' or 'Repost' option, and follow the prompts.