Can't get past prohibitory icon at startup

Prohibitory sign says, "I found MacOS, but some of its major components are missing or damaged, or the wrong version", and startup cannot continue.

You should repair your drive, using Safe Mode or Recovery then try again. If no joy, you will need to re-install MacOS.

PROVIDED there are no hardware issues, a Re-Install in place does not disturb your Files and Applications. But it re-writes over 350,000 files -- if your drive is shaky, this could drive it over the edge into failure.

hh50 wrote:

can't get past Prohibitary icon at startup. Tried everything, I've attempted to go to internet startup, but all I get this could take a while.

About the screens your Mac displays as it starts up - Apple Support

About macOS Recovery - Apple Support

In or out of warranty you can get a free over the counter 'Apple Service Diagnostics' test /assessment

Make an appointment for a "hardware issue"—

https://www.apple.com/retail/geniusbar/