RCON
RCON ("remote console") is a communication protocol supported by FiveM which allows you to remotely control the game server without direct access to the machine the server is running on. nfpm has full FiveM RCON support, allowing you to easily connect to the FiveM server remotely with nfpm rcon.
Commands
FiveM has a number of built in server commands which you can use as well as the following default NFive commands:
reload [<plugin>]Causes NFive to notify all, or specified, server plugins to reload their configuration from disk.
Creating Commands
NFive server plugins are able to register new commands via IRconManager which is available server side.