how to make easy pdf at home in phone laptop , mac etc.

 ok so this reading is only for students who are online struggling in saving the pdf and all materials, so to get, a good saver, there are so many apps those apps are not at all good, it's my personal experience, I also a student studying, if u want to know which class comment me to know the class, by the way, apps are good but not that reliable, I used ample of apps in android and mac also. but did not find any solution to it, ......but I m coming with cond=firmtion of apps so that u can easily be storing any pdf text or something writings, articles to your self, so let's begin \

GOOGLE DRIVE 

this is a particular app only designed for pdfs but if we update this app, we will get to know about more and more kinds of stuff, 

MICROSOFT ONENOTE 

APPS GIVEN GOOGLE PLAY

NOTES APP

GOOGLE NOTE

GOOGLE CALENDAR 

AND MANY MORE /......