If you are using PHONE PLUS to receive faxes and Metrofax to send faxes:
Your incoming faxes will arrive in your email account
And you can CLICK HERE for the details on how to send faxes.
If you are using PHONE PLUS with an analog adapter to send and receive faxes on your fax machine:
Your incoming faxes will arrive on your fax machine
you will send faxes from your fax machine