It's not an only noun phrase. The fragment consists on two noun phrases which are joined by the preposition "of". The first noun phrase is "the glow" where "the" is a determiner and "glow" is the noun, and the second noun phrase is "the soft candlelight", In this NP, "the" is a Determiner, "Soft" is an adjective, and "Candlelight" is a noun.
