The Second Beast has a name. He is called the False Prophet three times. Twice he is associated with the First Beast who is the Antichrist and once with the Dragon which is Satan.
The fact that he is called the False Prophet is proof that he is not the Antichrist.
Jesus was looking ahead when He said, "There shall arise False Christs and False Prophets and shall show great signs and wonders: insomuch that, if it were possible they shall deceive the very elect." Here Jesus shows a difference between False Christs and False Prophets so they cannot be the same.