Simple Invoice Payments on website?

I manually make my own invoices in an excel spreadsheet, and print and hand deliver them to my customers.

I currently have my square and paypal account linked to WIX. I want to set up a page where anyone can enter their Name, Invoice number and a custom dollar amount (So I don’t have to setup a database) to pay the invoice.

This way, I won’t have to collect emails from customers and make a second, online invoice to send to them. I want my customers to be able to go to my website at any time and send a payment.

Need some insight on how to do this please!