Treba mi kratak predah prije nego što nastavim raditi.

In this sentence, Croatian uses the very common pattern trebati + dative pronoun:

• treba mi = I need
• treba ti = you need
• treba mu/joj = he/she needs

Literally, it is closer to a short break is needed to me than to English I need a short break.

That is why the verb is treba and not trebam here.
Also, in this structure, the thing needed behaves like the grammatical subject:

• Treba mi predah. = I need a break.
• Trebaju mi nove cipele. = I need new shoes.

Notice how treba/trebaju changes depending on whether the needed thing is singular or plural.

Mi here means to me / for me, and it is the dative form of ja.

So:

• ja = I
• meni / mi = to me

In Treba mi kratak predah, mi shows the person who has the need.

The short form mi is unstressed and very common in normal speech. The longer form meni is used more for emphasis:

• Treba mi predah. = I need a break.
• Meni treba predah. = I need a break.

Because Croatian is not building this sentence the same way English does.

In English, I is the subject and a short break is the object:

• I need a short break.

In Croatian here, the construction is different:

• mi = the person affected, in dative
• kratak predah = the thing needed, in nominative

So kratak predah is in the nominative singular, not the accusative.

That is why the adjective and noun appear as:

• kratak = nominative masculine singular
• predah = nominative masculine singular

The normal form here is kratak predah.

Croatian masculine adjectives can sometimes appear in two forms, often described as indefinite and definite. In many everyday situations, learners will most often meet the basic form like this:

• kratak predah = a short break

The form kratki can appear in other contexts, especially when something is more specific or in certain stylistic patterns, but kratak predah is the natural neutral phrase here.

So for this sentence, just learn:

• kratak predah = a short break

They are similar, but not exactly the same.

• predah = a breather, a short rest, a moment to catch your breath
• pauza = a pause, a break, often a more practical or scheduled break
• odmor = rest, relaxation, sometimes even vacation/holiday depending on context

In this sentence, kratak predah sounds very natural because it suggests a brief pause before continuing to work.

So:

• kratak predah = a short breather / short break
• kratka pauza = a short pause/break
• odmor would sound broader or more general

Yes, prije nego što means before or more literally before ... followed by a clause.

Here it introduces the action that will happen later:

• prije nego što nastavim raditi = before I continue working

You can think of it as:

• prije = before
• nego što = than / that, as part of a fixed conjunction

In real Croatian, you may also hear prije nego without što, and it can still sound natural:

• prije nego što nastavim
• prije nego nastavim

Both are used, but prije nego što is a very standard full form.

Nastavim is from the perfective verb nastaviti, while nastavljam is from the imperfective verb nastavljati.

Here Croatian prefers the perfective present after a time expression like prije nego što when talking about a future next step:

• prije nego što nastavim raditi = before I continue working

Even though nastavim is present tense in form, it refers to a future action here.

Why not nastavljam? Because nastavljam usually sounds more like an ongoing or habitual process:

• Nastavljam raditi. = I am continuing to work / I continue working.

But in your sentence, the speaker means first I need a break, then I will continue, so nastavim fits better.

Because nastaviti is commonly followed by an infinitive when the same person continues doing something:

• nastaviti raditi = to continue working
• nastaviti učiti = to continue studying
• nastaviti govoriti = to continue speaking

So:

• nastavim raditi = I continue working / I go on working

Croatian could sometimes express similar ideas in other ways, such as with a noun phrase:

• nastaviti s radom = continue with work

But nastaviti + infinitive is very common and natural.

Because Croatian usually drops subject pronouns when they are already clear from the verb ending.

Here, nastavim already tells you the subject is I:

• nastavim = I continue

So ja is unnecessary unless you want emphasis or contrast.

Compare:

• prije nego što nastavim raditi = before I continue working
• prije nego što ja nastavim raditi = before I continue working

The second version sounds more emphatic.

The basic meaning stays the same, but the normal neutral order here is:

• Treba mi kratak predah.

Croatian word order is fairly flexible, but short pronouns like mi usually appear early in the sentence.

Possible variations include:

• Kratak predah mi treba.
• Meni treba kratak predah.

These are possible, but they shift the emphasis:

• Treba mi kratak predah. = neutral
• Meni treba kratak predah. = I need a short break
• Kratak predah mi treba. = It is a short break that I need

So the original sentence is the most natural neutral version.