Unable to add credit card to Apple Wallet

What message are you getting when you try to add a card to your Wallet?

Make sure you are in a supported region, as Apple Pay is not available in all markets. 

⇢ Countries and regions that support Apple Pay - Apple Support

Ensure that your card issuer and bank support Apple Pay. Below is a list of Apple Pay participating banks in different regions. 

⇢ Canada, Latin America, and the United States 

⇢ Africa, Europe, and the Middle East 

⇢ Asia-Pacific 

Make sure your region is set correctly.

⇢ Change the language and region on iPhone - Apple Support

⇢ Change your Apple ID country or region

Learn ⇢ If you can't add a card to Apple Wallet to use with Apple Pay - Apple Support for more information. 

I've been told by Apple Support that I cannot add a card to Apple Pay on my M4 Mac mini because I do not have a Touch ID Magic Keyboard.

"Apple Pay is not available on this Mac."

I cannot understand this because even if I had Touch ID there is an option to type in password.

Apple say: "Mac models introduced in 2012 or later with an Apple Pay-enabled iPhone or Apple Watch"

Add a card to wallet

Indeed. Follow my post above for guidance.