What must I do in my paypal account to accept a payment made through my jotform form

It depends if you're using standard PayPal or PayPal Pro, since in Standard you will need PayPal email (email that is tied to your PayPal) only and that's it, in Pro you will need API username, password and signature, you can read more in this guide: https://www.jotform.com/help/391-How-to-Integrate-Form-with-Paypal

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