To see all your visitors who have subscribed to your notifications, simply head over to the 'Subscribers' tab.
Here you can see an overview of your Subscriber count and growth. Scrolling further down, you can also see a geographical view of where most of your subscribers are located.
Along with this, you can also see the complete list of all your subscribers with labeled with a subscriber token.
You can also see their email ID if they logged into your store when they subscribed. But this feature is available only for Pro and Enterprise plans.