How to setup PayPal integration on my form?

Also, need help with setting up the paypal payment option integration at the bottom of the form - do I need an API from Paypal? or???

If you want to use the Standard PayPal, there is no need of API from PayPal. You can just connect using your PayPal email address. Please refer to the guide below that can help you with setting up an order form using PayPal.

https://www.jotform.com/help/165-Setting-Up-Your-First-Order-Form

If you want to receive payments using direct payments with Credit cards by PayPal Pro. Please take a look at the guide below that provides differences between PayPal and PayPal pro.

https://www.jotform.com/help/183-Difference-Between-PayPal-PayPal-Pro

Thank you!

I don’t have a product I need to set up in the Paypal integration as they registrants will register extra guests and a fee will be generated as a result. The paypal just needs to be a way for them to pay for the fees generated earlier in the form – how do I finish without this piece?
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In this case, you may pass the calculated value on a calculation widget to the payment field. Please go through the guide below that can help you with achieving this requirement.

https://www.jotform.com/help/275-How-to-Pass-a-Calculation-to-a-Payment-Field

Thank you!