Unable to open ibooks file in Pages
I have an ibooks file from an iBook I made back in 2017. iBooks author doesn't exist anymore (I just found out) so I have to use Pages. I am unable to open the iBook in pages. When I select the ibook and do file-open with, I select Pages from 'all applications' and get: The document "titlename.ibooks" could not be opened. Pages cannot open files in the "Electronic Publication (Apple Books)" format.
How am I able to edit this document or convert it to something else that has the same interaction functionality I built with it in iBooks?
MacBook Pro 15″, macOS 10.14