Við streymum þáttaröðinni núna.

Yes — here Við is the pronoun we.

Icelandic has:

• við = we (pronoun)
• við = with / by / against (preposition, depending on context)

They are spelled the same, so context tells you which one it is. In Við streymum þáttaröðinni núna, it has to be the pronoun we, because it is the subject of the sentence.

The capital V is only there because the word is at the beginning of the sentence.

A natural breakdown is:

• Við = we
• streymum = stream / are streaming (1st person plural present)
• þáttaröðinni = the series / the TV series (definite singular, here in the dative)
• núna = now

Very literally, it is something like:

We stream the-series now.

But in normal English, you would usually say We are streaming the series now.

Because it agrees with við = we.

The verb is streyma = to stream. In the present tense, the we form is streymum.

So:

• ég streymi = I stream
• við streymum = we stream

That -um ending is a very common Icelandic ending for 1st person plural verbs in the present tense.

Because Icelandic often uses the simple present where English prefers the present continuous.

So Icelandic:

• Við streymum núna

can naturally correspond to English:

• We are streaming now

The word núna = now helps make the ongoing meaning clear.

Icelandic can also use a progressive-style construction with vera að + infinitive, for example Við erum að streyma..., but the plain present is very common and often perfectly natural.

Because in this sentence the noun is in the dative, not the accusative.

That is one of the things English speakers often have to get used to in Icelandic: the object of a verb is not always accusative. Some verbs take dative objects, and here streyma is being used that way.

So:

• þáttaröðinni = the series in the dative singular definite
• þáttaröðina would be the accusative singular definite

Even though English just says the series, Icelandic has to choose a case form.

It is attached to the noun.

Icelandic usually adds the definite article as a suffix rather than using a separate word like English the.

So:

• þáttaröð = series
• þáttaröðinni = the series (in this case/form)

Because Icelandic nouns change for case, the definite ending also changes. That is why the definite form is not just one fixed ending in every situation.

Because it contains several pieces of information at once.

The base noun is þáttaröð, which is a compound:

• þáttur = episode
• röð = row / sequence / series

So þáttaröð literally means something like episode-sequence, i.e. TV series.

Then Icelandic adds more grammar onto it:

• the definite article
• the case ending

That gives you þáttaröðinni.

This kind of compact, built-up noun is very typical of Icelandic.

No. Its basic idea is related to streaming / flowing more generally.

Depending on context, streyma can refer to things:

• physically streaming or flowing
• people streaming somewhere
• media being streamed online

In this sentence, because the object is þáttaröðinni (the TV series), the meaning is clearly to stream a show/series.

Yes, but the word order may change because Icelandic main clauses usually follow the verb-second pattern.

The given sentence:

• Við streymum þáttaröðinni núna.

is a neutral, natural order.

You could also say:

• Núna streymum við þáttaröðinni.

That puts more emphasis on now.

Notice what happens there:

• when Núna moves to the front,
• the verb streymum comes next,
• and then the subject við follows.

That verb-second pattern is very important in Icelandic.

A rough English-friendly approximation is:

VITH STRAY-mum THOWT-ta-ruth-in-ni NOO-na

A few helpful sound notes:

• þ is like th in thin
• ð is like th in this (though at the end of a word it can sound weaker)
• ey in streymum is roughly like ay in say
• á in þátta- is roughly like ow in cow
• ú in núna is like oo in food

Also, Icelandic usually stresses the first syllable of the word, so:

• VIÐ
• STREY-mum
• ÞÁTT-a-röð-inni
• NÚ-na