You cannot "by-pass" a blackberry ID. If you do not have one you will need to create one from the phone.
Blackberry smartphone running BlackBerry 10:
To access BlackBerry ID settings from a BlackBerry 10 smartphone, follow the steps below:
1.From the home screen, swipe down from the top and select Settings.
2.Select BlackBerry ID
To change the id associated with the phone read this link How to change or update the BlackBerry ID Username (email address)