I am still a neophyte learning about the software. Where do I go to check which updater I have installed?If you have the 10.4.6 updater, then the only system you can update is 10.14.5.
You need the 10.4.6 combo updater, which will update any 10.14 system from 10.14 to 10.14.5 (and will also install on a system that is already updated to 10.4.6)
https://support.apple.com/kb/DL2010?viewlocale=en_US&locale=en_US is what you need.
Edit:I am still a neophyte learning about the software. Where do I go to check which updater I have installed?
Sounds simple enough except that I have no daggum idea as to how to do most of that outside of the download and moving to trash parts. lolYou need to reinstall Mojave.
Download the system installer from the App Store.
When the download is complete, the installer will automatically launch. Quit the installer at that time.
Use one of the methods to create a bootable USB installer. Copy the original installer app to the trash. Empty the trash -- you have it now on a USB installer.
And, finally, boot to that USB installer, and reinstall macOS. This time, it will change the SSD format to APFS.
And - that's it!
Your "apple certified tech" can help you with that
But, as I said, there are several methods that you can use.
You can download and run the easy DiskMakerX - which takes you step by step through the process (no strange commands to type in the terminal) You can get DiskmakerX here - https://diskmakerx.com