trying to install ventoy on internal HD

[Midas]

Is it possible to install on an internal hard Drive that is not USB? I thought from reading that is possible but maybe I am missing something.

I can confirm that install to HDD works, as I have a couple of systems running it.

I can suggest that -- if you can't make Ventoy work with your HDD but have a working USB -- you could use Macrium Reflect to copy the two partitions from the USB to the HDD, then resize the first partition without touching the second; report back if it boots or not...