Add required checkbox to my account page

Hi!

I am looking for a way to add a required checkbox when a costumers wants to make an account. It should say: Ik ga akkoord met het de verwerking van mijn persoonsgegevens door Natuursteen Stefano en heb de privacy verklaring gelezen.

which means something like: i agree with the privacy policy

Does someone know a way to do this?

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