If you would like to always BCC yourself, you need to either use VBA or a utility as Outlook’s rules can only CC an address.
See To automatically Bcc all outgoing messages (Outlookcode.com) for a VBA code sample or Automatically BCC All Messages (slipstick.com) for a list of utilities you can use to always BCC an address.
Published August 18, 2009. Last updated on June 7, 2021.