How can I create an option to allow

1. How do I set up a renew now button that can be hosted on our form and sent as a link through email?

2. How do I manually add a new subscriber and by pass the payment option?

I am not sure if I understood your question correctly. Do you want to add a custom button to your form? You can only add a hyperlink button to your form that will redirect your users to some other page. On this thread, you can find how to achieve it:

https://www.jotform.com/answers/1097290 

Regarding the second question - You can un-require the payment field or hide it so that you can submit the form with making a payment. Another option is to import the data.

Import App: Easily Import Your Excel or CSV Data into JotForm

If I did not understand your questions correctly, please explain in more details what are you trying to achieve and provide us a link of the form you are working on.