Vi øver på pusteteknikken så vel som intonasjonen.

Øve is the infinitive form, meaning to practise.
Øver is the present tense, meaning practise / are practising.

So:

• å øve = to practise
• vi øver = we practise / we are practising

A useful thing to remember is that Norwegian present tense often covers both the English simple present and present continuous. So Vi øver ... can mean either We practise ... or We are practising ..., depending on context.

Because å øve på noe is the normal pattern when you mean to practise/work on something.

So:

• øve på uttale = practise pronunciation
• øve på grammatikk = practise grammar
• øve på intonasjonen = practise the intonation

The på is not random; it belongs to the way this verb is commonly used. English does something similar with expressions like work on.

Så vel som means as well as.

In this sentence, it links two things that are being practised:

• pusteteknikken
• intonasjonen

So it means that both are included.

It is a correct and natural expression, but it can sound a little more formal or written than simpler alternatives like og or både ... og.

The endings -en and -en/-n here show the definite singular, so the nouns mean:

• pusteteknikken = the breathing technique
• intonasjonen = the intonation

Norwegian often uses the definite form when the thing is understood from the context, even in places where English might sometimes use a more general noun.

Here, the sentence suggests a specific breathing technique and a specific intonation relevant to the exercise or lesson.

If you used the indefinite form instead, it would sound more general:

• Vi øver på pusteteknikk og intonasjon = we practise breathing technique and intonation in general

Both are normally common gender nouns in Bokmål:

• en pusteteknikk
• en intonasjon

When a common gender noun becomes definite singular, it usually gets -en:

• en pusteteknikk → pusteteknikken
• en intonasjon → intonasjonen

So the -en ending is doing the job that English does with the separate word the.

Because in Norwegian, the definite article is usually attached to the end of the noun.

So instead of saying something like the intonation with a separate article, Norwegian often says:

• intonasjonen

Likewise:

• pusteteknikken

You only add a separate article like den in certain structures, especially when there is an adjective:

• intonasjonen = the intonation
• den gode intonasjonen = the good intonation

It is a compound noun, which is very common in Norwegian.

It can be broken down like this:

• puste / pust = breathing / breath
• teknikk = technique

Together: pusteteknikk = breathing technique

Then the definite ending is added:

• pusteteknikk → pusteteknikken

A very important pattern in Norwegian is that compound nouns are usually written as one word, not two.

Yes. A very natural alternative is:

Vi øver på både pusteteknikken og intonasjonen.

That means almost the same thing and is often a bit more straightforward in everyday speech.

A rough comparison:

• så vel som = a little more formal or written
• både ... og = very common and clear in speech and writing

There is no exact English equivalent, but a good starting point is:

1. Start with a vowel somewhat like e in bed
2. Round your lips as if you were going to say oo

That gives you something close to Norwegian ø.

For øver:

• stress is on the first syllable: Ø-ver

English speakers often find ø difficult at first, so it is completely normal if it takes practice. The most important thing is to notice that it is a different vowel from o and u.