How do you find out if someone has deleted you from your Instagram friends list?

If you were at a moment where you try and see the posts of any of your friends, but you are not able to access their profile then there is a solution to that.
This person may have locked their account forever or, unfortunately, they have blocked your profile.

If the Instagram user profile is set to 'private' then that person's name will not appear in the search list; however, this may mean they either have blocked or deactivated their Instagram account.
There is no legal way to understand if this person has blocked you on Instagram, but there are some third-party solutions and applications you can use.
One option is to create a new account on Instagram and then simply use the 'Search' function by setting the user name in the Search / Search bar. If you show the person's profile, then it's almost certain they've blocked you from their friends list.