Note: If you delete the app, you will not cancel the subscription!
Cancelling the subscription prevents you from the subsequent charges. However, that doesn't refund your last payment.
To check or cancel subscriptions on your Mac, do the following:
Open the App Store on your device.
Click the sign-in button or your name at the bottom of the sidebar.
Click View Information at the top of the window. You might be asked to sign in.
On the page that appears, scroll until you see Subscriptions, then click Manage.
Click Edit next to the subscription that you want to cancel.
Don't see the subscription that you're looking for?
Click Cancel Subscription.
If you don't see Cancel Subscription, the subscription is already cancelled and shouldn't be renewed.