Ok you're making some progress but maybe I could make things easier for you.
Since you're using POP, Outlook stores all your information - emails, contacts, calendar, notes etc in a file with the extension PST. The default location for this on Windows 10 is as follows:-
C:\Users\{Insertnamehere}\AppData\Local\Microsoft\Outlook
If you go to this folder in File Explorer you will see files like this:-
Outlook.pst
Archve.pst
(In fact if you were using IMAP then there would also be files ending in OST - which indicates Offline files)
So in order to backup your emails etc just copy everything in the Outlook folder to your backup device.
(Outlook.pst is all your personal files. Archive.pst is where Outlook archives old stuff. It does this automaticaly to limit the size of the Outlook.pst file. I think it does this for emails over 6 months old but I believe you can set the limit to what you want.)
The other advantage of doing this is that if/when you come to switch to a different version of Outlook (or some other email client) you only need to replace the default files of the new installation with the files from your backup and off you go.
This is what I did a few years back. I had Office/Outlook 2007 but because it was getting long in the tooth and no longer supported (security could be a problem), I went to MS365. After a year or two I got fed up with the constant updates not to mention the subscription payments. I bought a genuine copy of Office 2019 from Amazon for about £10 - today Office 2021 is available for about £35.
After setup just copied all my backup Outlook files to the default location of the new version and that was it.
You're probably aware but I'll mention it anyway:-
Within Outlook you can create folders to organise your emails. So for example I have a Folder for Amazon emails; one for Ebay; one for CAMC and virtually any on line 'shop' we use. Just makes life easier finding things.
One final thing - since its likely that you have a default installation of Windows, all your data - documents, pictures, music and videos are also stored in the C:\Users\{Insertnamehere} folder. So its good practice to backup this folder as well.
Hope this helps