Do you have to be a certain age to use Apple Pay?

Yes. 18 yrs. old.

This is incorrect. The only requisite is to have an Apple ID (13+ in most countries), although many banks set their own restrictions as to who can open an account and which accounts can be used with Apple Pay.

The question is about Apple Pay, not an Apple ID. No bank will issue a credit card to a person under 18 years of age.

Debit cards can also be used with Apple Pay however, which banks definately issue for under 18s.

But only if the person has a valid bank account, adequate funds, and a limited debit card.

Why are you trolling this topic? You are not contributing anything useful to the OP, but are disrupting the topic by directing posts to me just to argue.

I am not arguing, simply answering the OP's question by stating that there is no minimum age to set up and use Apple Pay. This is regardless as to whether there are adequate funds in the account, which is down to the individual bank concerned.