Apple Pay with Siri

If it's a restaurant bill, I would say yes provided the restaurant accepts Apple Pay. You must firstly make sure there are sufficient funds in the account registered with Apple Pay.

If the bill is from, say, a utilities company, check first whether they accept Apple Pay.

This may explain it all. The link is Apple Developer's: https://developer.apple.com/documentation/sirikit/payments

It would appear that you can use Siri. Here's the link: Send, receive, and request money with Apple Pay - Apple Support

Scroll down to just below the Apple watch. It's all explained there. It's not much, but allegedly, it should work.

A little bit depends which iPhone you're using. Apple pay doesn't work on iPhone 5 (all variants). Beyond that, I can't help you. Other responders may be able to help if they know which iPhone you're using. Good luck.