[split] Linux ... (CommunityAuth)

When I enter "wine" in Ubuntu Software I get "No Application Found" but if I enter window there is "XTerm" (which appears close) among 3 others.

I'm thinking Wine just doesn't happen to be pre-installed with your Linux distribution of choice. Find its package manager and it should be easily installable from there.
Though, trying to open Wine itself as a program is ... I can't come up with the exact word, so I'll just say it serves only for environment configuration. It is otherwise pretty transparent and just does its magic when you try to execute a Windows executable.

There is no mention of Wine within XTerm. But if I click on the icon it says "standard terminal emulator for the X window system".

Just to clear up potential confusion - the "window" word in that quote doesn't refer to Microsoft Windows. XTerm is not what you're looking for.

I understand "wine" means "Wine Is Not an Emulator". I'm confused.

It's a tongue-in-cheek recursive acronym, and Wine is indeed an emulator. The name originally came from "WINdows Emulator".
Similarly, PHP originally stood for Personal Home Page, but is now "PHP: Hypertext Preprocessor".

Don't pay attention to that.

If I click "Launch" a DOS window appears referring to "sudu_root" which is something I know nothing about, but I'm studying https://www.linux.com/blog/how-use-sudo-...troduction. I note your reference to "sudo" in referring to text editor but I don't understand.

DOS, you should probably know, is an operating system on its own (and speaking of acronyms, it stands for Disk Operating System). What you see is not DOS, just a similarly-looking command line prompt - a terminal - probably powered by Bash.

sudo is not a text editor, but a version of the WAC controls you're probably used to in Windows - a utility that asks for a password before allowing administrator privileges for a program's execution.

I'm using UltraEdit, a program I bought about 15 years ago. I find it absolutely magic and there is not very much I do each day without involving UltraEdit.

Haven't heard of it, but good for you if you like it so much.

The problem is though, much like the rest of your comments, this shows that you're waaay to reliant on old habits, and you kind of need to let go of them if you want to use Linux.

While Windows and Linux are both operating systems - and in that sense alone, indeed just the same - they don't really work in the same way and are fundamentally different under the hood. If you'll be doing all or most of your work with Windows software - just stick to Windows, there's no point in pushing an emulator to its limits for the sake of it.