"What kind of country is Norway?"
Translation:Millainen maa Norja on?
Absolute beginner here, so my understanding is very rough and I can't explain why.
Basically this question expects an answer like "Norja on ADJECTIVE maa" (Norway is an ADJECTIVE country), and so the question asks "Millainen maa Norja on" (What kind of country Norway is?). This is the purpose of olla.
As for the order, Finnish is generally Subject Verb Object, and it just so happens that the Subject Verb order is retained even in questions, except when it's a question starting with olla + ko (onko, oletko, etc); in those questions specifically the order is more natural for an English speaker — "Onko Norja ADJECTIVE maa?" (Is Norway an ADJECTIVE country?). Why does the order work like this - I don't know.
To confuse things further, spoken everyday Finnish could easily include the sentence "onko norja millanen maa?" By and large I'd advice you not to sweat too much about the word order, if you went around asking "millainen maa on Norja" or "millainen on maa Norja" people would understand just fine, even if the sentences could sound slightly odd :)
With questions starting with "olla + ko" you mean yes / no questions, i. e. question that need "yes" or "no" as an answer. In this kind of question, the word order is more like in English (Are you a Finn? = Oletko (sinä) suomalainen?". But in questions starting with an interrogative pronoun (what / who / where / when / why / ...) the word order is like in a statement (Where is the dog? = Missä koira on?).