Which directories contain start scripts for services on FreeBSD?

The directories that contain start scripts for services on FreeBSD are /usr/rc.d/ and /usr/local/etc/rc.d/. The /usr/rc.d/ directory contains the system-provided scripts for the base system services, such as cron, sshd, syslogd, etc. The /usr/local/etc/rc.d/ directory contains the scripts for the additional services installed from ports or packages, such as apache, mysql, nginx, etc. These scripts follow the BSD rc.d framework, which allows for fine-grained control and customization of the startup process. The scripts are invoked by the main /etc/rc script, which sources the /etc/rc.conf file for configuration options

https://docs.freebsd.org/en/articles/rc-scripting/