iPad Air series 5 2017 transfer of files?

[Willabong]

I have an iPad Air and no idea how to transfer my e-pub book folder containing about 2 gig of e-pubs from Microsoft onedrive to the iPAd.
I can access them from the cloud because MS onedrive is synced to my iPad, but what I want to do is access the e-pub files from the iPad home screen when I am using the iPad off line?

This may be a basic question for a long time user, but I have only recently bought the iPad, so any help (walk through) would be appreciated very much!

 

[Raz0rEdge]

Import the ePubs into iTunes as ebooks and then you can sync them to your iPad and access them using the iBooks app on there.

 

[Willabong]

I will give it a try, thanks for your advice!