How do you cancel Apple Arcade

How to cancel a subscription on your iPhone or iPad

1. Open the Settings app.
2. Tap your name.
3. Tap Subscriptions.
4. Tap the subscription.
5. Tap Cancel Subscription. You might need to scroll down to find the Cancel Subscription button.

If you want to cancel a subscription from Apple - Apple Support

If you have Apple One Subscription then see the pic below which is self-explanatory