You can use /f help to get some information on factions commands and what they do When you first join you will want to get your starting kit using the command (/kit starter) or /kits and select the from the available options.
OP-Factions is a game mode which consists of 'Factions' basically, clans where you can ally with other Factions and help each other defend your bases and help each other at PVP fights, or enemy them and you can try to raid them/target them at PVP fights
