What does 50 Cent mean in the song by get atcha Tupac pretend. put that to an

The line "50 Cent get atcha Tupac pretend" from The Notorious B.I.G.'s song "Get Atcha" is a reference to the rap rivalry between Biggie and Tupac Shakur. Biggie is accusing Tupac of being fake and pretending to be a gangster when he is not.