as far as SMTP is concerned there is no difference between a TO, CC or BCC
if you are using UTL_SMTP, you simply add another call to UTL_SMTP.RCPT, regardless of how you want to them to be displayed (or not displayed in the case of bcc)
if you want the recipient to be displayed as Cc: then in the mime header you label them as such instead of a "to"
UTL_SMTP.write_data(p_conn, 'Cc:' || 'your_cc_recipient@address.com' || UTL_TCP.crlf);
if you are using UTL_MAIL, you simply populate the cc parameter to the send procedures