how to set up icould drive?

Unless I'm misunderstanding, Apple really need to have a look at the way iCloud Drive is set up, and also perhaps, what it is called.

To start with, I searched for info on this website for "how to set up iCloud Drive" and get loads of hits on "iCloud" but not "iCloud Drive". But there are lots of help files all over the web entitled "Whats the difference between iCloud and iCloud Drive?". It would help solve all this confusion if Apple gave it a less confusing name! Even the iCloud sub-window entitled iCloud Drive has a line at the top saying "Apps that store documents and data in iCloud will appear here". ...? Do they mean iCloud Drive?

Now my further confusion;

When you start a new user account, the set up process leads you towards using iCould Drive, and if you delve deep you find that Desktop and Documents folders will be turned on. And it immediately starts uploading all your files and removing them from your hard drive. My Documents folder contains over 70GB of work, so even if I pay to max out my iCloud Drive to its 50GB capacity it still won't hold all my stuff. And actually, I don't want to pay for storage... 5GB is free and that's more than enough for my calendars, notes and contacts. (or is that iCloud?)

So now I have that whole thing of having to re-download my own files.. Oh and if I just turn off iCould Drive, the files have disappeared from my hard drive.

Did somebody think this through?