Hey there info1874,
Welcome to the QuickBooks Community! Thanks for reaching out to us here. QuickBooks is a great software to have. It has a variety of features that can help make running your business easier. The Payments feature is one of them. I would be happy to point you in the right direction.
In order to have access to the Pay now in the invoices, you will need to apply for the Payments feature. Here is a helpful article that will provide additional information on Payments. It will also show you how to apply for Payments feature.
If you have any other questions, feel free to reach out here.