How can I add a Paypal link for people to order a book on our website

I have created a seller's questionnaire in Jot Form.  After the opening paragraph, I want two buttons.  

1. leads them to purchase our book Get Top Dollar for Your Real Estate

2. leads them to the questionnaire and they get our book for free

I am not sure how to create these if then scenarios or how to enter a PayPal link to our website where they can order our book.  Can you please advise?

You can have these in the form by configuring emails and conditions. Add a Single choice element that would ask people if they want to purchase or get the book for free.

Next, set up a conditional logic to show Paypal field if they wish to purchase and set up another conditional logic to show other fields when they would like to have the book for free. In this case, either Paypal or group of fields will show up based on the selected option. You do not need to setup HIDE condition because fields are hidden by default when SHOW condition exists.

https://www.jotform.com/help/316-How-to-Show-or-Hide-Fields-Base-on-User-s-Answer

https://www.jotform.com/help/196-Hide-or-Show-Multiple-Fields-at-Once 

You can also set up multiple autoresponder emails to send a customized email based on the selection.

Guide to create autoresponder: https://www.jotform.com/help/26-Creating-a-Form-Autoresponder

Guide to set up the conditional email: https://www.jotform.com/help/167-How-to-send-to-a-specific-email-address-based-on-a-selection.

Note that we do not offer a one time download link, so you'll have to find a way to secure the link and prevent others from sharing it.