Below is a quick summary of everything showcased in the Video
Click on "Reports"
Click On "Create Report" and "Audience Overlap".
Type in the Instagram handles for which you wish to see the stats.
After you click on "confirm", you will see the profile pictures of the inserted Instagram accounts so that you can make sure you have correctly typed in the handles. If all the profiles are correct, click on "Confirm Report".
It can take up to 24 hours for a report to be generated. You can check the status of your reports under "My Reports". Once it is ready, the status will be shown as "Completed".