The only official and accurate way how to view private Instagram followers is to send them a follow request. It might take time before they accept your request, but once they do, you will see the list of their followers, their posts, and other details.

Simply type in the person's username and search. Or you go to the Instagram profile of the person you're looking for, click their name in the search bar at the top of the page. To the right, you'll see the user's followers list. From here, you can search for the person you're looking for.

Creating a Finstagram, also known as a fake Instagram account, is a popular method to follow someone without alerting them. It allows me to view content without directly engaging or leaving a trace.