How do you link your form on the internt.

How do you link your form on the internt.using example, www.paypal.com

Do you want to embed your form? OR Do you want to integrate your form with PayPal?

Basically this guide provides you information on how you can protect your form and give access to only certain persons with the help of a password.

Here you can check a few related guides:

https://www.jotform.com/help/50-PayPal-Forms 

https://www.jotform.com/help/34-Embedding-a-Form-to-a-Web-Page 

Do review and let us know if you are referring to something else.

Nice answer, but how will I get a webpage
...

By webpage, I meant, if you have any existing website where you want to embed the form. If you do not have one and want to embed a form on a webpage, you would need to create a webpage first.

You have many options to create a webpage such as WordPress.