FortiExplorer and Console are two different ways.What you need is a
console cable that you can find it in the box.Then connect it to Console
Port of FortiGate.If your client does not have serial port you can
connect it to a Serial to USB convector.So...
Everything that you can not find it ;)Usually there is no need to enable
features like VDOM in SOHO models, so Fortinet hide that.You can
download CLI refrence.If you want to configure something and it's not on
the GUI use that.