There is multiple authors to who wrote the bible, see below for who wrote what:
Matthew: Himself
Mark: Himself
Luke: Himself
John: Himself
Acts: Luke
Romans to Hebrews: Paul
James: Himself
Peter: Himself
John: Himself
Jude: Himself
Revelation: John
Where John was the apostle John, not John the Baptist. James and Jude was Jesus' brothers.
