Utedoen står langt fra vannkilden.

Because Norwegian usually writes compound nouns as a single word.
Here, utedo is a compound:

• ute = outside
• do = toilet / loo

So utedo means outhouse or outdoor toilet. Then -en is added to make it definite:

• en utedo = an outhouse
• utedoen = the outhouse

In Norwegian, the definite article is often attached to the end of the noun instead of being a separate word.

So:

• utedoen = the outhouse
• vannkilden = the water source

This is very common in Norwegian. English says the before the noun, but Norwegian often puts the definiteness at the end.

Står is the present tense of stå, which literally means stand.

In Norwegian, it is very common to use verbs like stå for the position or location of things, especially:

• buildings
• objects standing upright
• fixed structures

So Utedoen står ... literally means The outhouse stands ..., but in natural English we usually translate it as The outhouse is ...

Using står sounds more idiomatic than er here because an outhouse is a physical structure with a location.

Yes, that would be understandable, but står is more natural in this context.

• står focuses on the physical placement/location of the structure
• er is more general and less specific

So Utedoen står langt fra vannkilden is the more idiomatic choice when talking about where a building or structure is located.

Here, langt means far, and it functions adverbially, not as an adjective directly describing a noun.

Compare:

• en lang vei = a long road
  
  • here lang describes the noun vei
• Det er langt = It is far
  
  • here langt describes distance in a more adverb-like way

In står langt fra, Norwegian uses langt to express distance: far from.

So:

• lang = long
• langt = far / a long distance

Fra means from.

In this sentence, it is part of the expression langt fra, which means far from.

Examples:

• langt fra huset = far from the house
• langt fra skolen = far from the school

So langt fra vannkilden means far from the water source.

Yes. Vannkilden comes from the compound noun vannkilde:

• vann = water
• kilde = source

So:

• en vannkilde = a water source
• vannkilden = the water source

Again, Norwegian prefers writing compounds as one word.

Because the sentence refers to specific things:

• the outhouse
• the water source

Norwegian marks that definiteness on the noun itself:

• utedoen = the outhouse
• vannkilden = the water source

This often happens when the speaker assumes the listener knows which outhouse and which water source are being talked about.

No, this is a very normal Norwegian statement pattern:

• Utedoen = subject
• står = verb
• langt fra vannkilden = adverbial phrase of place/distance

So the structure is basically:

Subject + verb + distance/location phrase

That is quite similar to normal English word order, even though some of the details, like står and the definite endings, are different.

The base forms are:

• utedo → dictionary form of utedoen
• stå → dictionary form of står
• lang → base adjective behind langt
• fra → already the basic form
• vannkilde → dictionary form of vannkilden

So if you were looking these up in a dictionary, those are the forms you would usually search for.