Various people wrote the Catholic bible; no one person did it, although all were inspired and ultimately we consider God to be the ultimate Author of the Bible. We don't even know who wrote many of the books, for example, the Book of Hebrews.
According to Vatican II, Dei Verbum, the Dogmatic Constitution on Divine Revelation of the Second Vatican Council, which is authoritative for Catholics,
Those divinely revealed realities which are contained and presented in Sacred Scripture have been committed to writing under the inspiration of the Holy Spirit. For holy mother Church, relying on the belief of the Apostles (See John 20:31; 2 Timothy 3:16; 2 Peter 1:19-20, and 2 Peter 3:15–16), holds that the books of both the Old and New Testaments in their entirety, with all their parts, are sacred and canonical because [they are] written under the inspiration of the Holy Spirit, they have God as their author and have been handed on as such to the Church herself. In composing the sacred books, God chose men and while employed by Him they made use of their powers and abilities, so that with Him acting in them and through them, they, as true authors, consigned to writing everything and only those things which He wanted. (#11)
Catholic Church, "Dogmatic Constitution on Divine Revelation: Dei Verbum," in Vatican II Documents (Vatican City: Libreria Editrice Vaticana, 2011)