use OBS v28 download OBS v28 https://github.com/obsproject/obs-studio/releases/tag/28.1.2

or download here obs-studio-28.1.2-macos-arm64.dmg

open OBS press Start Virtual Camera

Screen Shot 2023-09-06 at 2.08.48 PM.png

make sure obs-mac-virtualcam.plugin

obs-mac-virtualcam.plugin.zip

is in the folder (/Library/CoreMediaIO/Plug-Ins/DAL) Finder → Go

/Library/CoreMediaIO/Plug-Ins/DAL