How do i add the payment section to a form when accepting PayPal?

I inspected one of the forms on your account and I saw that it is integrated with Paypal Standard. Do you want to add a payment section with credit card fields to your form? This is possible with Paypal Pro and Paypal Express integrations:

How to Integrate Form with Paypal Pro

Configuring PayPal Express Integration

Difference Between PayPal and PayPal Pro

If I did not understand your question correctly, please explain in more details what are you trying to achieve. 

Thanks.  I would like to use PayPal Express.  I can't seem to find on PayPal the API information

Here is a useful guide which shows you the steps to obtain your Paypal Apı Credentials:

https://www.jotform.com/help/284-How-to-Obtain-PayPal-API-Credentials

If you still need assistance, please do let us know.