なんという + [noun] + だ / だろう なんと + [i-adj / na-adj + な] + [noun] + だろう なんと + [i-adj / na-adj / verb (plain)] + のだろう / ことか なんて + [i-adj / na-adj + な] + [noun] + なんだ なんて + [noun] + だ
なんという, なんと and なんて open an exclamation: "what a…!", "how…!". なんという goes straight before a noun; なんと goes before an adjective or a whole description; なんて is the casual form of both. The sentence closes with だろう or でしょう, or with のだろう or なんだ.
Straight after a noun or a clause, なんて is a different word, "things like" – a separate point.
なんと … ことか is the most literary ending: "how very…!". It follows the plain form, with な after a な-adjective.
These go beyond the exclamation.
At the head of a sentence, なんと with a comma announces a surprising fact.
なんという also asks what something is called.