Can I split one page into multiple sub pages?

Hello,
as you can see in the link, I have this one page which shows all its sub pages as a list in alphabetical order. The number of these sub pages will grow further and I don’t want to display them all on 1 page. Is it possible to “split” that page into multiple pages but have it still count as the same, single page? I basically just want an 1/x…2/x navigation at the bottom, but I need the urls to stay the same.

I am a noob btw. Is there a plugin for this? Or would a different approach be better?

The page I need help with: [log in to see the link]