There is a "pin numbers" app in Fusionpbx. The app is disabled by default.
Go to Advanced>Menu Manager edit "default" menu (or the menu you are using)
Find "PIN Numbers" under the Applications section. Add the user groups that should be able to see the page. (superadmin and maybe admin)
Check Advanced>Group Manager permissions for the selected groups to have proper permissions to view/edit pin numbers.
Log out
Log in.
The "PIN Numbers" app should be available in Applications.
Visit
docs.fusionpbx.com for information on how to add the pin number check to your dial plans.