Runes in the historical record served writing and charms rather than a set oracle. In the modern revival Nauthiz is read for need, constraint, hardship, patience and the strength found under pressure. These associations are a product of the twentieth-century reconstructionist and esoteric movement rather than the ancient testimony, and are presented as a symbolic tradition, not as prediction.
Nauthiz is one of the runes where all three surviving poems point in a broadly consistent direction, hardship that nonetheless carries the possibility of instruction or benefit if endured rightly, and the modern divinatory keyword tradition follows this attested sense fairly closely, reading Nauthiz for need, constraint and the endurance such constraint can teach. As with the other runes, this reading as a divinatory sign for a querent is a twentieth-century development rather than a continuation of any ancient oracular use.
The Armanen-descended rune-magic tradition transmitted into English chiefly through Thorsson's work also treats Nauthiz as usable actively rather than only read passively: chanted aloud as galdr, or carved into wood, metal or a bind-rune combining several staves, for an intended practical effect. No source earlier than the twentieth century attests any such active magical use of this specific rune, and the practice should be understood as a modern reconstruction built on the reconstructed name and the rune poems rather than as a recovered ancient technique.