I just looked up a brief history. It was invented by two different men at two separate times in the late 1700s - one man in Sweden and another man later in England. However it wasn't bottled and mass produced until the 1800s in the USA. Seeing as it was called "soda water," then the term "soda" makes sense. Btw, in the States, restaurants refer to soda as "soft drinks."
I entered "He is drinking coffee and soda" and was correct, but in english it has a different meaning from "He drinks coffee and soda". The first means he would actually have a coffee and soda on hand which he is currently drinking. While the latter I would take to mean that he does at times drink coffee and soda, but he is not necessarily drinking either at the point in time the sentence is said.
It's the general term for flavoured and sweetened carbonated drinks. Sparkling water would be called "mineralvann" or "vann med kullsyre".
In recent years, "flavoured sparkling water" has made it's appearance in the stores, and this is basically sparkling water with added flavour but no sweetener, which is generally less carbonated than soda. Farris is one of the main Norwegian brands offering this.
What's the gender for "brus"? According to bab.la, it can be masculine or neutral depending on whether it's meant generally or as carbonated water, which I think is overlapping. So which is it? (https://en.bab.la/dictionary/english-norwegian/soda)
Again, that's very much an older person's term in many areas. Much more common (at least in Manchester and Norfolk) is to just hear the name of the kind or brand of drink (a lemonade, a coke, etc). In my experience, a good rule for Americans can be to assume all the things you get told 'the British' (whoever they are) call things are probably not true for most people. There are more differences in dialect from where I am to the other side of my city than are present in some whole languages, especially in vocabulary, and the term 'Britain' in technical usage covers 5 countries.
Lemonade is a lemon flavoured flat or carbonated drink. If carbonated, it would be referred to as "sitronbrus" in Norwegian, and if not, it would be called "limonade" (generally made from fresh lemons) or "sitronsaft" (made from some sort of concentrate, often with artificial flavouring).
"Brus" is the general term for soda.
I've actually a story concerning this: When I was in Norway last time, I was shopping grocerys one day. Being a native speaker of the German language, which has a lot in common with the Norwegian, I decided to buy a bottle of "saft", which would be juice in Germany. "Saft" in Norway, this is what I learned that day, is a very sugary concentrate of juice. At least this is what I guess from the taste. It was impossible to drink without mixing it with water... I asked my host what it was and even she couldn't really explain it, but told me that if I wanted to buy juice, I should just buy "juice" - That it was lemonade, is one thing I can not believe either, tho :)
So "brus" can translate as "soda" or "cola" - however, Duolingo only seems to accept "soda" as an answer?
And to jump on another argument, in Scotland "pop" seems to be rarely used - "fizzy drink" might be on occasion but most people seem to refer to most of these beverages as "juice", even if it is carbonated! :P