Launch agents and daemons locations in macOS

/Library/LaunchAgents
/Library/LaunchDaemons
/System/Library/LaunchAgents
/System/Library/LaunchDaemons
~/Library/LaunchAgents

To stop a service permanently

sudo launchctl unload -w [path to .plist file]

Related links

Quite old but mostly accurate:
How to remove unneeded startup services?

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