Some NAB version bibles have commentary and footnotes by Father Raymond Brown. This priest holds to some rather controversial views regarding scripture that appear in places to disagree with authentic Catholic teachings.
One of these ideas that Father Brown favors is the idea of a “Q” source for all the Gospels. That is that the Gospels are nothing more than just plagiarized versions of one document. There is absolutely no evidence to support the idea of “Q” but it has caught on in some circles. It is popular because it explains how the Gospel accounts written over many years and very different geographical locations, can be so similar without having to rely on the power of God to inspire the writers. Proponents of the “Q” idea also tend to be those who reject the belief that the Bible is inerrant and that many of the accounts, such as the Nativity narratives or the story of the Exodus are nothing more than fiction. These are contrary to the teachings of the Catholic Church.
Personally, I would find another version of the NAB that does not use commentary by Father Brown. It can lead you astray as it has lead others, including some members here on this forum.