Modify the checkout-site where the note-Box is

Hi there

i am using the twentytwentyone-theme and woocommerce. In one of the checkout-sites there is a box called “Bestellhinweise (optional)” in which people can add individual notes to the order. in that Box there is a grey text. That text as well as the title of the box and of the whole section “Zus?tzliche Information” in the checkout-site I would like to modify. Can you help me how i can do that?

cheers
Dani

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