How can I refund something from a year ago

I seriously doubt Apple is going to refund you for something you purchased a year ago, but start here -

Request a refund for apps or content that you bought from Apple -

https://support.apple.com/en-us/HT204084

Refunds, when they are granted, can be no more than 90 days after the charge. And there is no guarantee that Apple will refund any charge; they are not required to by the terms of use of the iTunes & App Store (“all sales are final”), and if they do refund it is as a courtesy.