Not sure about the age requirements or other account specifics, etc. But it seems like you should be able to use Apple Cash for allowances and such
From the FAQ:
>How do I add money to my Apple Cash card?
>If you’re under 18, money is added to your Apple Cash card only when someone sends you money.
From the FAQ: >How do I add money to my Apple Cash card? >If you’re under 18, money is added to your Apple Cash card only when someone sends you money.