This ICloud account cannot be used for Apple Pay what will I do?

Good morning, if you are from Europe, you can use Apple Pay when you will be at least 16 years old. Second

possibility can be that, you are not on Apple Pay support countries. I had this problem too. If you are on list of supported countries and you have been at least 16 years old - go to this website and call the support.

phone numbers:

https://support.apple.com/cs-cz/HT201232

Is the account setup as a child account ?

If yes, because of legal stuff you cannot setup Apple Pay with a Child younger than 16 or 18

Additionally, Apple Pay is not supported everywhere.

Countries and regions that support Apple Pay - Apple Support