To send a form to more than one recipient email account:
Open freeform.php and add two or more email addresses to one of the recipient properties, separating each address with a comma.
Select the Submit button on your form, and set its send to property to the desired recipient.
Publish and test your form online. In the above example, when the Submit button is clicked, the form will be sent to both a@b.c and x@y.z (CC carbon copy).
Notes
Some hosts require all recipient email accounts to be hosted on the same domain as the form, and will not deliver form emails to external addresses.
If two email addresses point to the same email account (e.g. an alias or catch-all account), the host may deliver just one email.