To list all installed ports (pre-compiled software packages) on a FreeBSD system, you can use the pkg package manager.
To list all installed ports, you can run the following command:
# pkg info
This will list the name, version, and origin of all installed ports on the system.
To list only the names of the installed ports, you can use the -a option:
# pkg info -a
To list only the installed ports that belong to a particular category, you can use the -g option followed by the category name:
# pkg info -g <category>
Replace <category> with the name of the category, such as databases, mail, or www.
For more information about the pkg command and managing software packages on a FreeBSD system, you can refer to the FreeBSD documentation and the pkg man page by running man pkg on the command line.