Will I get a refund if I cancel subscription on the same day of purchase?
I cancel a subscription the same day of purchase do I get a refund I was charge for a whole year
Canceling a subscription does not undo the transaction. It just stops future fees.
Purchases for in-app subscriptions on Apple devices may be refundable as described here:
Request a refund for apps or content that you bought from Apple - Apple Support
Also see: Check the status of an approved refund - Apple Support