Re: My e-Book won't open on my MacBook Air
Am no expert in this area, yet your request for help deserves some response.
Wondering if the e-book is stored in iCloud so it can be read on all devices and computers with the same Apple ID.
or
Reading an e-book on Mac may be slightly different to reading one on a device.
See how to: Read books in Books on Mac - Apple Support
or
If you did not download the e-book directly from the store to the Mac, It may be that the e-book was purchased on an iOS / iPadOS device, and is not in a format that MacOS understands.
If necessary: you could try downloading the e-book directly to your Mac:
See: Download purchased and updated books or audiobooks in Books on Mac - Apple Support