Did John Baptist go to heaven after he died?

Yes.
There was not a greater man that John the Baptist, according to Jesus. He was the forerunner of Jesus who was the Messiah. John was a born again believer so, of course, he went to heaven.

Matthew 11:11 (KJV) Verily I say unto you, Among them that are born of women there hath not risen a greater than John the Baptist: notwithstanding he that is least in the kingdom of heaven is greater than he.

Luke 7:28 (KJV) For I say unto you, Among those that are born of women there is not a greater prophet than John the Baptist: but he that is least in the kingdom of God is greater than he.

Jesus, however, was greater than John the Baptist because Jesus was God.

John 5:36 (KJV) But I have greater witness than that of John: for the works which the Father hath given me to finish, the same works that I do, bear witness of me, that the Father hath sent me.