Issue on Install - Booting Up

I recently flashed the Rosseta Fold for COVID .iso onto my USB (FFC) after flashing I plugged the USB into my PC then Booted it up, it then displayed the logo for Balena Etcher, after that I went out to do somethings for my parents. When I came back all I saw was a black screen, and my Pc was shut down, I went to turn my PC back on but it didn’t boot up all that displayed was an underscore “_” on the top left corner, any help. This PC is my life. I also tried to enter the BIOS but it didn’t open.

If you followed the instructions for “Main Computer”, then you don’t flash anything but download and configure an app to run in the background.

However… If you followed the instructions for “Laptops and Desktop computers” then this is a complete image and will wipe your system - there is a big warning in red at the top of the screen to stop you doing this if you have come to the wrong place.

Please can you check which instructions you followed?

Is the one I followed