What is the problem?
I installed Raspberry Pi OS on my second PI because I can't seem to get them both set up.
Can I now install Octoprint without having to erase the software and put a new image on the SD card?
What did you already try to solve it?
serial.log or output on terminal tab at a minimum, browser error console if UI issue ... no logs, no support! Not log excerpts, complete logs.)
Additional information about your setup
OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible