Actually, this is incorrect. The Jewish Scriptures known as the Tanakh (the Old Testament) existed before the time of Jesus. The Catholic Church started with the Apostles upon the death of Jesus. The last New Testament scripture wasn’t completed until almost 100 AD (the Book of Revelation). The “Bible”, a definitive, canonized compilation of all of these scriptures in a single volume and in a single language, did not exist until the late 300s AD, after it was compiled by the Catholic Councils of Rome, Carthage, and Hippo.
Between the death of Christ and the compilation of the Bible, there was much confusion as to what books were to be included in the Bible. Many people dismissed books like Revelation and 2 Peter. Others included books like the Didache, the Epistle of Barnabas, and the Shepherd of Hermas. Others included the Gnostic Gospels, such as the Gospels of Thomas, Mary Magdelene, and Philip. There were even completely forged “folktale” stories floating around, such as the Infancy Gospel of Thomas. Further, the Jews had not canonized the OLD Testament at this point, and so there was discussion over whether to use the Hebrew version of scripture, or the Greek Septuigant, which included seven extra books (The Deuterocanon / Apocrypha). Amidst all of this confusion, it took the Catholic Church to sort everything out and come up with the definitive list of what was to be included (although general agreement DID already exist upon several books, such as the four main Gospels).
You’re right, the Catholic Church did not “write” the Bible, but it DID compile scripture into what became known as the Bible.