What is the finance rate if I want to buy an Iphone 12

You would have to apply for the Apple Card first. Finance charges are based on your creditworthiness but Apple also offers interest-free plans if you buy an Apple product that qualifies. Goldman Sachs is the card issuer and sets the rates.

If you choose Apple's Citizen's One Loan, it's 0% for 24 months.

If you choose Apple Card issued by Goldman Sachs, it's 0% for 24 months.

You can apply from any computer, iPhone or iPad.