Notochord and Backbone and Spinal cord all same plz clarify soon !!

NO, these are different from each other.

Notochord is the chief distinguishing feature of Chordates, which is a dorsal longitudinally rod. It lies between the dorsal nerve tube and the gut. It increases locomotory power and internal support. It probably evolved originally in the swimming larval forms of chordate ancestors. It still resembles something like its original form in few remaining group of non vertebrate chordates, but in most chordates it is mainly replaced during embryonic development by bony vertebrae of the vertebral column, or backbone.

Spinal chord- It acts as the link between the brain and the nerves that strtch through out the body. Spinal chord is protected by a bony, vertical rod with several curves called the vertebral column (backbone).