How to create and deploy content to Ionic app from external file(s)?

Hi all devs!

So, the idea is simple: I would like to have an app with possibility to download external content. The app will be used as “student book” for learning purposes (text, picture).

I am looking for a simple solution for users: be able to create content (outside the app), then upload this file(s) to the cloud (maybe Google drive?), run the mobile app, insert link to the file and the app will download the file and show it. Once downloaded, the file will be saved and used from phone storage next time.

Any ideas how to…?