I have a 3B+ with the camera module which works great, but my prints come out terrible through Octopi so I wanted to setup a virtual printer for timeplapses but I am not understanding how to find the YAML file. I have the plugin installed and I checked the SD card but there are no YAML files there. Am I missing something?
nano ~/.octoprint/config.yaml
Basically, the period at the begining of that folder name hides it from the average ls command. You might try ls -a to show "all".