Looks like you have HS up and running.
BUT
WHERE did you install to?
IMPORTANT:
Did you ERASE the ENTIRE internal drive first?
In reply 54 above, I see a graphic that says "MacOS High Sierra will be installed on the disk "OS X Base System'".
But that ISN'T where the main OS is supposed to go.
The proper way to do a fresh install like this is to:
1. Boot from the USB installer
2. Open disk utility
3. IMPORTANT - go to the "View" menu and choose "show all devices"
4. In the list on the left, choose the topmost entry which should be the physical drive itself.
5. Now, erase it to APFS.
6. Then, quit disk utility and open the OS installer
7. It will install "from scratch" where it's supposed to go. Typically, this is "Macintosh HD".
It looks like the install flash drive is good.
So...
I suggest you "do it over again", but this time exactly as I've suggested above.