No worries… in that case if you’re new and able to install plugins, I strongly suggest you install PluginManager and KanboardSupport.
PluginManager shows the Offline plugin as rather old, so as a new user I would not bother with it.
PluginManager (for plugins) and KanboardSupport (for settings and troubleshooting) will help you a lot to understand your system and install plugins with more information to hand.