Skiftnøkkelen ligger i originalemballasjen.

The ending -en marks the definite singular form, so it works like English the.

• en skiftnøkkel = an adjustable wrench
• skiftnøkkelen = the adjustable wrench
• en originalemballasje = an original package / original packaging
• originalemballasjen = the original packaging

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

Because Norwegian often uses ligge for the location of physical objects.

So:

• Skiftnøkkelen ligger i originalemballasjen sounds natural for an object that is physically located somewhere.
• Skiftnøkkelen er i originalemballasjen is understandable, but it is less idiomatic in this kind of context.

A useful pattern is:

• ligge = be lying / be located
• stå = stand / be standing
• sitte = sit / be situated
• være = be

Norwegian likes these more specific position verbs more than English does.

It can mean both, depending on context.

Norwegian does not usually use a separate progressive form the way English does. So the present tense ligger can correspond to:

• lies
• is lying
• sometimes more generally is located

That means one Norwegian form often covers two English possibilities.

I means in / inside.

Here it is used because the wrench is inside the original packaging:

• i originalemballasjen = in the original packaging

If something were on top of something, Norwegian would more likely use på instead.

Because Norwegian writes compound nouns as one word much more often than English does.

So:

• skiftnøkkel is one compound noun
• originalemballasje is also one compound noun

This is very normal in Norwegian. English often writes similar ideas as two words, but Norwegian usually joins them together.

It is one compound noun, not an adjective plus a noun.

That is important because original does not behave like a separate adjective here. The whole word is a single lexical unit:

• originalemballasje = original packaging
• originalemballasjen = the original packaging

If you wanted a structure with a separate adjective, you would need something like:

• den originale emballasjen = the original packaging

So the sentence uses a compound noun, not an adjective-noun phrase.

The sentence has normal Norwegian main-clause word order:

• Skiftnøkkelen = subject
• ligger = verb
• i originalemballasjen = prepositional phrase showing location

So the pattern is:

Subject + verb + place

That is the same basic order English would usually use here.

A useful thing to know: if you move the place phrase to the front, Norwegian keeps the verb in second position:

• I originalemballasjen ligger skiftnøkkelen.

If you want to look them up, the basic forms are:

• skiftnøkkel — noun
• ligge — verb
• originalemballasje — noun

The forms in the sentence are inflected:

• skiftnøkkelen = definite singular of skiftnøkkel
• ligger = present tense of ligge
• originalemballasjen = definite singular of originalemballasje

Both nouns are normally treated as common gender nouns in Bokmål, so their indefinite form takes en and their definite singular form ends in -en.