from the area of nursing home aka maternity home aka hospital where the baby was born, 1st you get hospital certificate with date & time of birth with parents name exactly as on cnic, then you move to that area UC office they issue a birth certificate with parents name & cnic numbers with reference details of baby from the hospital and parents address as on CNIC, that you take to NADRA office with parents cnic copies - 21 days is time from NADRA for the B form - ( did for a neice in 2008 if its different now please excuse me )
i see you asking address for UC in clifton somewhere in thread it is near old cotton & cotton outlet at clifton, the by-lane which connect entry from cardeals show room to boat basin eatries