i have a problem to add cards on apple wallet

Are you in a country or region that support Apple Pay?

Places that support Apple Pay - Apple Support

Does your financial institution support Apple Pay?

Apple Pay participating banks in Asia/Pacific, Africa, Europe Latin America, Middle East and United States - Apple Support

Confirm your region is set correctly.

Change the language and region on iPhone - Apple Support

Change your Apple ID country or region

If you get the Learn More popup, that takes you to the support document you posted from when tapping on the (➕) icon in the Wallet App, then make sure your iPhone is set to a country or region where Apple Pay is

supported in Settings➜General➜Language & Region➜Region.

click here ➜ Countries and regions that support Apple Pay - Apple Support

Otherwise, explain exactly what "problem" you are having.