A good online store?

I'm looking for a good, free and reputable online storage for university scripts etc., because I do not always have to lug my laptop back and forth or an external hard drive. Now, however, I have never used online storage before, so unfortunately I have no idea about it. My hope is that someone can recommend a good one or tips on what I should pay attention to.

Google Drive gives you 15gb, mega even 50gb are both free. The best thing would of course be your own nas or a nextcloud. An sFTP server would do the same. You would know exactly where your data is.