Relationship between receivable transaction and custom object in page

Hello Gurus,

I've created a custom object where I use the field CUSTOMER_TRX_ID to extend information from AR invoices. How can I make it so that on the AR invoices screen, with a button or link, a pop-up or fullscreen screen of the custom object opens, referencing the customer_trx_id of the invoice with the customer_trx_id of the created custom object?

I hope it's clear what I mean. I'm not sure if my proposal is too far-fetched. If anyone thinks that information can be presented in another way, I welcome suggestions.

Thank you very much!!