OctoPi change hostname before first boot

I'd like to see this added to https://octoprint.org/download/ in the Setting up OctoPi section. Furthermore, I'd suggest that the file always exist in the OctoPi image with the default name "octopi".

I am afraid i am not getting this at all, my initial raspberrypi is running great and i have done as you suggested on the second raspberrypi but when i type in the IP address all i get is this!
Screenshot_20211107-173740_Chrome|243x500

I have never set up a octoprint setttings for my second pi so therefore have no username or password. Assistance is greatly appreciated, thank you