Musikeren er berømt.

Because -en is the usual definite singular ending for many masculine nouns in Norwegian.
So:

• en musiker = a musician
• musikeren = the musician

In this sentence, musikeren means the musician, not just a musician.

In Norwegian, the definite article is often attached to the end of the noun instead of standing as a separate word in front.

So English says:

• the musician

But Norwegian often says:

• musiker + en → musikeren

That final -en already contains the meaning of the.

Er means is / am / are, depending on context. It is the present tense of the verb å være, which means to be.

Examples:

• Jeg er = I am
• du er = you are
• han er = he is
• musikeren er berømt = the musician is famous

Unlike English, Norwegian does not change this present-tense form according to the subject. It stays er.

Berømt is an adjective, and here it means famous.

In the sentence Musikeren er berømt, it comes after er and describes the subject:

• musikeren = the musician
• er = is
• berømt = famous

So the structure is:

• subject + verb + adjective

This is the normal word order for a simple statement in Norwegian:

• subject + verb + complement

So:

• Musikeren = subject
• er = verb
• berømt = complement/adjective

This is very similar to English:

• The musician is famous

Norwegian main clauses usually keep the verb in the second position, and in this sentence the subject comes first, so the verb naturally comes next.

Usually, no, not as a natural standalone sentence.

En musiker means a musician, but in a sentence like this, Norwegian would usually prefer:

• Musikeren er berømt = The musician is famous
• En musiker er berømt could sound incomplete or unusual unless the context clearly requires a musician rather than the musician

If you want to say something more general, Norwegian often uses:

• Musikere er berømte = Musicians are famous
  or
• En musiker kan være berømt = A musician can be famous

So Musikeren er berømt is a very natural sentence, while En musiker er berømt depends much more on context.

Yes, adjectives in Norwegian can change form depending on grammar.

For berømt, common forms include:

• en berømt musiker = a famous musician
• et berømt band = a famous band
• berømte musikere = famous musicians
• den berømte musikeren = the famous musician

But after er, adjectives are often seen in a basic predicate form, as in:

• Musikeren er berømt

So here berømt is exactly the form you would expect.

The letter ø is a vowel that does not exist in standard English. It is pronounced somewhat like the vowel in French bleu or German schön.

A rough guide:

• be- sounds like beh
• rømt has that rounded ø sound, with your lips rounded more than for a normal English vowel

Very roughly, berømt may sound something like beh-RURMT or beh-RUHMT, but no English spelling matches it exactly.

The ø is the main thing to pay attention to.

A rough pronunciation guide is:

• moo-see-keh-ren

A few notes:

• u in mu- sounds like oo in food
• the stress is usually on si: mu-SI-ke-ren
• the final -en is pronounced clearly, though often lightly in natural speech

So it is not pronounced exactly like the English word musician. It has four syllables: mu-si-ke-ren.

In standard Bokmål, musiker is usually treated as a masculine noun, which is why you commonly see:

• en musiker
• musikeren

However, in modern Norwegian, many nouns referring to people can be used in a gender-neutral way in practice. The grammatical gender of the noun is still usually masculine in the dictionary, but the word itself can refer to a person of any gender.

So musikeren can mean the musician, whether the musician is male, female, or another gender.

In Norwegian yes/no questions, the verb usually comes first.

So:

• Musikeren er berømt. = The musician is famous.
• Er musikeren berømt? = Is the musician famous?

This is similar to English, where is moves before the subject.

Yes. Berømt most directly means famous, but depending on context it can also be translated as well-known, renowned, or sometimes celebrated.

So the core idea is that the person is widely known.
In most beginner contexts, though, famous is the best and simplest translation.

The indefinite version would be:

• En musiker er berømt.

Grammatically, that means A musician is famous.

But as mentioned earlier, this may sound less natural without context, because it raises the question: which musician? or do you mean musicians in general?

So the sentence you were given, Musikeren er berømt, is often the more natural and clearer example.