Is there a way to manually add their info without submitting payment

There are a few people that are not tech savvy to submit the online application. Is there a way to manually add their info without submitting payment

Do you want to fill and submit the form for those users, without making the payment?

Considering that your payment field is required that is not possible. However, you can turn OFF Required option and then fill and submit the form without making a payment.

Another way is to import the data. You will have to create an Excel or CVS file and add the data of those users there and then import the data using this app - http://import.jotform.io/ 

Inside of this guide, you can find how to import your Excel or CSV data:

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