Can I use a CC or BCC in a campaign?
You can add a CC address to the campaign email and it each email generated in the campaign will be sent to the provided email address as CC. You currently cannot customize the CC address using personalization/spreadsheet values.
You can send each campaign email to a BCC email address. Do not set the BCC on the campaign email itself (as you would for CC), but instead find the BCC setting in the MailMerge365 plugin. Every email send in that campaign will automatically be sent to the provided email as BCC.