I iMac crashed and I can't recover it?
Late 2012 recent mohave upgrade. Crashed so that it took up to 1 minute to respond to any click. Called Apple support spent an hour on the phone:
Safemode: won't happen, just shuts back off
Local recover boot: reinstall OS Doesn't work says "macOS could not be installed on your computer An error occurred while removing the previous system...try again"
Internet recovery boot: reinstall OS same as above.
I just want to clear and reinstall OS...I have my data backed up.
What should I do next?
Should I "delete" the HD from disk utility?
MacBook Pro 15", macOS 10.13