It rolled out a few days ago, but you might not have noticed it, or maybe you haven’t updated the app on your phone yet. If you don’t have it yet, UPDATE YOUR INSTAGRAM APP!
Also, it’s only currently available for iPhones 6S and up, and Android phones from 2015 and newer. Instagram is working on adding the feature to more phones. So for now, if you have an older iPhone or a kind of obscure Android, you might be out of luck.