Add the new Formula for exact form to the Form

Hi, very beginner here, I'm struggling with the instructions for creating exact form , I'm at step 14, I saved a basically empty exact form and I just want to add a print button to a form I have as a proof of concept before adding variables to the exact form. But I can't seem to find what step 14 is talking about. Any help is very appreciated.

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Ayoub Salhi
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