Wow, first time I used 4 S's... reminds me of Saylor, Sophia, StraighterLine, Study.com... anyways, here goes... A few people have asked me about storage space to keep their documents. I have been only recommending Onedrive (Hotmail) and G-Drive (Google)... I also tell people about dropbox but there is "limited" space for all of these... is there something more that they can get? How about, say from Yahoo or another provider like github?
Some ideas here, from Dr. Johann von Googlefinger (was rocket scientist - now Cloud guru): https://www.techradar.com/best/best-cloud-document-storage Canadian one here: https://www.sync.com/business-cloud-storage/?_m=pep&gclid=EAIaIQobChMI2a_irI219QIVFY1oCR0dLQYJEAAYASAAEgIhXfD_BwE https://www.carbonite.com/ https://www.pcmag.com/picks/the-best-cloud-storage-and-file-sharing-services
Since You Asked: Yahoo Mail provides 1 TB of storage - that could be a LOT of docs! For email and possibly other uses. Their own explanation is here. https://www.ymail.info/ymail-gives-us-up-to-1-tb-of-free-storage-how-to-use-it.html GitHub is not for cloud storage - or is it? Their own story here. https://github.community/t/can-i-use-github-as-free-unlimited-cloud-storage-or-is-this-only-with-bitbucket-possible/1574
It's more of a DIY option, but you may want to consider NextCloud. You'll have to set it up initially yourself (and host it somewhere), but then you have a ton more control and privacy. For those just wanting to back up but not necessarily access their content non-stop, Sia might be something worth looking into as well. Lastly, for now, you could also check out Spider Oaks storage solutions. This is another privacy-centric option.
Also presumably more secure than the free services, the people behind ProtonMail have ProtonDrive now as well: https://protonmail.com/blog/proton-drive-early-access/