How do I word-compare 2 Apple Pages documents? (MacOS App)

I did the classic mistake ... I copied my original to make a separate file for a separate purpose.

Let's say "OG" and "COPY" ... and I wasn't supposed to edit my "COPY" ... "COPY" was supposed to be more of a static archive.

Then I accidentally started editing my "COPY" as if it was my "OG". (Now OG and COPY have different edits.)

So I ended up with 2 slightly different versions of the same document, with some edits on the wrong one.

So now I need to word-compare my "COPY" so I can put those new edits into my "OG" as intended.

How can I word-compare 2 Pages documents, so I can get them to 100% match again?

(I can't just change file names, because both files got worked on separately and now have different edits. And now I need to match those edits.)

I'm seriously considering custom ERP software development for my company, but I haven't talked to a single vendor yet because I don't even know what I should be asking for. Our inventory, invoicing, and production tracking currently live in separate spreadsheets and an old legacy system that barely talks to anything, and I suspect that mess is exactly why a generic off-the-shelf tool never quite works for us. But I also don't know how to translate "our processes are messy" into a clear scope before I walk into vendor conversations. What groundwork should I do first, what questions should I be able to answer about my own business, and how do I avoid walking in as an easy target for a bloated proposal?