Using iCloud Drive

I was looking for an RTF editor but maybe I should ask just how to use iCloud Drive because that may be my trouble.

With iCloud Drive enabled on all devices, how does one add or access a document using an iPhone or iPad? If I try to add an RTF document I get an error message saying it failed to import, it must be in plain text.

I've tried Text Editor as well as Voice Dream Writer (which apparently cannot import RTF).

Would appreciate it if someone could walk me through the basics. The end goal is to edit RTF documents. Thanks.

Forum: 

Dropbox

Create a dropbox account. That will create a folder on your desktop. What files you put in that folder will show up in the dropbox app too. Now using the file browser on the iPhone you can visit the dropbox folder and copy files to your Icloud account.

No Dropbox

No no no. (smiles) Dropbox has a limit of 3 devices under its basic plan. iCloud does not have such a limit. So let us work out this issue with iCloud Drive.

file sharing

It's supposed to be possible to share files between windows pc's and apple devices,
but I have never got it to work. I mean directly device to device over your
local network. I can do this in linux, but not in windows.

Leaving Windows out

Leaving out Windows for the moment. on the iPhone, I cannot seem to open an RTF document on iCloud Drive. If I can resolve this, that would be fantastic. Using TextEditor, I can't open an RTF without getting the error. Or Voice Dream Writer opens to its file manager even though it no longer has access to iCloud Drive.