Longtime user. The old Pi that I have been using is beginning to feel a little crusty (like me ;-)) so I ordered a new Pi 5 as an upgrade. Went to load it but the imager only lists Octopi for Pi 4 and not Pi 5. Will anything bad happen if I lie and say I am running a Pi 4? Don't really want to order an older model since I have this huge collection of retired Pi(s).
The RPi 5 requires Debian 12 (bookworm). I believe RPi 4 requires 11 (bullseye). Older RPi models can use 12, 11 (bullseye), or even 10 (buster).
The current OctoPi release is based on Debian 11 (bullseye) so it won't work on an RPi 5.
What you can do is install bookworm on your RPi 5 and use octoprint_deploy or you can also get the 32bit nightlies here or the 64bit nightlies here.
See https://octoprint.org/download/ for more info.
ocotoprint_deploy is nice. Unfortunately they don't caution you that the pi has to be all wired up for this script to work well. I was trying to setup the new system while the old one was still running. Starting over.. 
Running on Pi5 using Bookworm and octoprint_deploy
Not happy with the Webcam config. No matter what I put for resolution it seems to be showing a pretty low res image. Useable but not as much detail as I should be getting.
I have an RPi 5 but no suitable camera so I'm afraid I can't help you with that. You could open an issue on the octoprint_deploy github if that's where the camera config came from.
Don't think it's specific to the deploy script. Webcam configuration seems to be a common topic in the forums. I tried diving into the configuration files but they all seem to have the right numbers in them For some reason the image on the main page looks very low res compared to the 5MP that the camera is putting out.
Try setting the resolution to the exact size of the sensor.