If you want to cancel the subscription from Apple, kindly follow the below steps:
 - Open the Settings
 - Tap on your name and click on subscription.
 - Click on "Cancel Subscription" option.
You might need to scroll down to find the Cancel Subscription button. If there is no Cancel button, the subscription is already canceled.
You can refer cancel subscription steps from the link attached aswell: https://support.apple.com/en-us/HT202039