How do you get around the 3MB upload limit?

I’m trying to upload an education certificate from my Muay Thai gym, which came as two PDFs. The system only allows a single PDF, so I combined them—but now the file is 4.9MB, which is over the limit.

I’ve tried compressing it in Canva, but the quality becomes too low to read. I also tried exporting the pages as images and resizing, but I’m still struggling to get it under 3MB.

It’s a 10-page document.

What documents should I check from a Muay Thai gym before I pay them the full fee for a 6-month membership, eg biz registration?

For those that go with the soft power options (Muay Thai training in particular), how do you get with the gym to have them creating the docs for you? Do you fly to Thailand to pay them directly, or can it somehow be done online prior to your flying there?