Time Machine Backups I am doing a clean install of Mojave on my MacBook - it has simply not been possible to upgrade from High Sierra to Mojave automatically.
I understand that it will overwrite all of the HDD contents
I know I can simply copy document files etc and then copy them back into the new system
But, will a Time Machine backup from the original High Sierra be able to reinstall all of my programs?
Thanks for the help. The problem turned out to be both more complicated and simpler than I originally thought.

I had installed a Tar Disk in 2015 and more research showed that quite a few users were having the same problems and error messages as I was.

I followed the instructions here - https://www.tardisk.com/pages/uninstall-sierra - to uninstall the Tar Disk - NOT removing it because I was coming from High Sierra, as the instructions said. It DID NOT solve the problem.

I then went through the whole rigamarole again; shut down my MacBook and physically removed the Tar Disk. I then reopened the Disk Utility and reformatted the internal Mac SSD - installed Mojave from a USB and it seems to have worked.

To answer my PRECISE question - now that Mojave is installed - Time Machine has been able to recover/reinstall all of my files and programs

Thanks again to those of you who responded