Improvisasjonskurset begynner nå.

Because Norwegian usually writes compound nouns as one word, where English often uses two or more words.

So Improvisasjonskurset is built like this:

• improvisasjon = improvisation
• kurs = course
• kurset = the course

Together, improvisasjonskurset means the improvisation course.

This is very normal in Norwegian:

• språkkurs = language course
• sommerkurs = summer course
• musikkurs = music course

In compounds, the last part is the main noun, and that is the part that takes the definite ending.

The -s- is a linking sound/letter often used in Norwegian compounds. It does not have a separate meaning here.

So:

• improvisasjon
• • linking -s-
• • kurset

becomes improvisasjonskurset.

This linking -s- is very common, but not fully predictable from English. You often just learn it as part of the compound:

• arbeidsdag = workday
• livsglede = joy of life
• verdensdel = continent

So in this sentence, the -s- is just part of how the compound is formed naturally.

In Norwegian, the is often expressed by an ending on the noun instead of a separate word.

Here:

• kurs = course
• kurset = the course

So Improvisasjonskurset already includes the meaning of the improvisation course.

This is different from English, where you would say the course as two words. In Norwegian, you often attach definiteness directly to the noun.

Because kurs is a neuter noun in Norwegian.

For a neuter noun in the singular:

• indefinite: et kurs = a course
• definite: kurset = the course

If it were a masculine noun, you would often get -en in the definite singular. But since kurs is neuter, the definite ending is -et.

So:

• et kurs
• kurset

That is why the compound ends in -kurset.

Begynner is the present tense of the verb begynne = to begin / to start.

So:

• å begynne = to begin
• begynner = begin(s), is beginning

In this sentence, begynner means begins / is starting.

A useful thing to know: Norwegian verbs do not change for person the way English verbs do. The same present-tense form is used with all subjects:

• jeg begynner
• du begynner
• han/hun begynner
• vi begynner

So begynner stays the same.

Nå means now, and in a simple statement like this it often comes after the verb phrase.

So this word order is very natural:

• Improvisasjonskurset begynner nå.

That is basically:

• subject: Improvisasjonskurset
• verb: begynner
• time adverb: nå

This is a normal Norwegian main-clause pattern.

Yes, absolutely. That is also correct.

Norwegian is a verb-second (V2) language in main clauses. That means the finite verb usually comes in the second position.

So you can have:

• Improvisasjonskurset begynner nå.
• Nå begynner improvisasjonskurset.

Both are correct, but the emphasis shifts a little:

• Improvisasjonskurset begynner nå.
  More neutral: talking about the course, then saying it starts now.

• Nå begynner improvisasjonskurset.
  Gives a bit more emphasis to now.

What you generally would not do in a normal main clause is keep the subject before the verb after fronting nå:

• Nå improvisasjonskurset begynner ❌

It can often cover both ideas, depending on context.

In Norwegian, the simple present tense is used more broadly than in English. So begynner can correspond to:

• begins
• is beginning
• is starting

In this sentence, English would most naturally often say:

• The improvisation course is starting now or
• The improvisation course begins now

Both match the Norwegian well.

A rough English-friendly guide would be:

im-pro-vi-sa-SJONS-kur-set be-GYN-er no

A few helpful points:

• sj in -sjons- sounds like sh
• y in begynner is a rounded vowel that English does not really have; it is not the same as English y in yes
• å in nå is roughly like the vowel in British law, though not exactly

Very roughly:

• Improvisasjonskurset ≈ im-pro-vi-sa-SHONS-kur-set
• begynner ≈ be-GYNN-er
• nå ≈ noh

The exact pronunciation depends somewhat on dialect, but that approximation will help you recognize it.