Thanks for your question.
There are many Christian denominations. Most claim to base their beliefs on the Bible. But do they?
The Mormons: They have their own prophet, Joseph Smith and the "Book of Mormon" apart from the Bible
The Seventh Day Adventists: They have their own "Prophetess" Mary Ellen White and her writings apart from the Bible
The Catholic Church: They have the "Infallibility" of the church and the "authority" of the Pope and hierarchy apart from the Bible.
The Christian Scientists: They have their own "Prophetess" Mary Baker Eddy apart from the Bible
The Evangelicals and Pentecostals: They believe they have the "Holy Spirit" apart from the Bible
The Jehovah's witnesses: They have their "inspired" hierarchy in Brooklyn New York and their writings apart from the Bible and they also have their own version of the Bible to support their beliefs.
The Christadelphians base their beliefs on the Bible alone.
I hope you have found this helpful