Many people say that there are no words that start with the velar nasal [N]. That's wrong. There's ''Ngami''. Look on a globe of the Earth or in a dictionary and see. Ngami is really a name but it still starts with the velar nasal [N]. i.e. [Na:mi(:)].
lots of Mäori words start with ng.
I think that what those many people are actually saying is that there are no words in English which start with [N].
Jim, ''Ngami'' is the name of a river. It's just as much of an English word as ''Iraq'' and ''Qatar''.
Also, If someone invented something and called it a ''ngee'' and pronounced it [Ni:] then would there be an English word that started with [N].
[N] and [x] rarely start words and [w], [j], and [h] rarely end words. But, that doesn't mean never.
Let's say that speakers of various languages have shared notions of what is "possible" phonetically in their language. In English, it is not normal to start a word with the velar nasal (though it is normal to end them with it, as in "sing"), but this is acceptable in many African languages, along with Tagalog and Maori. Similarly, words in Hungarian do not normally start with consonant clusters, while they do in most Germanic and Slavic languages. Seen from this point of view, I think even if English uses Ngami as a name, speakers will not perceive it as an English word, because it "violates" the phonetic rules of English (I am using "violates" figuratively, of course). It is never likely to become a household English word, but if it ever does, it will perhaps be tailored to sound more English.