Večeras ću kuhati juhu za djecu.

In Croatian, ću is a clitic (a short unstressed word), and clitics usually go in the second position of the sentence or clause.

So:

• Večeras ću kuhati juhu za djecu. = natural
• Ja ću večeras kuhati juhu za djecu. = also natural

But:

• Večeras kuhati ću... = not correct in standard Croatian

A useful rule is: the first stressed element comes first, and then clitics such as ću, sam, je, se usually come right after it.

This is the future tense in Croatian.

It is made with:

• the auxiliary htjeti in its short form: ću
• • the infinitive: kuhati

So:

• ću kuhati = I will cook

Other forms are:

• ćeš kuhati = you will cook
• će kuhati = he/she/it will cook
• ćemo kuhati = we will cook
• ćete kuhati = you (plural/formal) will cook
• će kuhati = they will cook

In this sentence, the subject ja is omitted because Croatian often leaves out subject pronouns when the verb form already makes the person clear.

Yes. Both are used.

You can say:

• Večeras ću kuhati juhu za djecu.
• Večeras ću kuhat juhu za djecu. — common in speech
• Kuhat ću juhu za djecu večeras.

A very important pattern:

• If the auxiliary comes before the infinitive, the infinitive is usually kept in its full form: ću kuhati
• If the infinitive comes before the auxiliary, it often drops the final -i: kuhat ću

So:

• Ja ću kuhati
• Kuhat ću

Both mean I will cook.

Večeras means tonight or this evening, depending on context.

It is an adverb of time.

Examples:

• Dolazim večeras. = I’m coming tonight.
• Večeras ću ostati kod kuće. = Tonight I’ll stay at home.

It is different from:

• večer = evening
• uvečer = in the evening

So in your sentence, večeras tells you when the cooking will happen.

Because juhu is the accusative singular form of juha.

• juha = nominative singular
• juhu = accusative singular

Here, soup is the direct object of the verb kuhati: you are cooking the soup, so Croatian uses the accusative.

Compare:

• Juha je gotova. = The soup is ready.
  (juha = subject, nominative)

• Kuham juhu. = I am cooking soup.
  (juhu = direct object, accusative)

This is very common with feminine nouns ending in -a:

• kava → kavu
• voda → vodu
• večera → večeru

Because djecu is the accusative form, and the preposition za normally takes the accusative.

So:

• djeca = children (nominative)
• djecu = children (accusative)

In this sentence:

• za djecu = for the children

This noun is a bit tricky because djeca is an irregular collective noun.

Useful forms:

• djeca = children (nominative)
• djece = of the children (genitive)
• djeci = to/for the children (dative/locative)
• djecu = children (accusative)

So za djecu is correct because za requires the accusative here.

Good question. English for can correspond to different Croatian structures.

In your sentence, za djecu is perfectly correct and means for the children / intended for the children.

But Croatian can also express this idea with the dative:

• Kuham juhu za djecu.
• Kuham djeci juhu.

Both can mean I’m cooking soup for the children.

The difference is often one of style or nuance:

• za djecu emphasizes for the benefit/use of the children
• djeci is an indirect-object construction, often very natural in everyday Croatian

So both are possible, but the sentence you were given uses the very common pattern za + accusative.

Yes, but that is normal in Croatian.

Croatian often drops subject pronouns because the verb form already shows the person:

• ću kuhati already tells you it means I will cook

So:

• Večeras ću kuhati juhu za djecu.
• Večeras ja ću kuhati juhu za djecu.

The first is much more natural unless you want extra emphasis.

You would add ja only if you want contrast or emphasis:

• Ja ću kuhati, a ti ćeš pospremati.
  = I will cook, and you will clean up.

Yes. Croatian word order is fairly flexible, although not completely free.

Possible versions include:

• Večeras ću kuhati juhu za djecu.
• Ja ću večeras kuhati juhu za djecu.
• Juhu za djecu ću kuhati večeras.
• Za djecu ću večeras kuhati juhu.

These all express roughly the same basic meaning, but the emphasis changes.

For example:

• Večeras first = emphasis on when
• Za djecu first = emphasis on for whom
• Juhu first = emphasis on what

The only thing you must be careful about is clitic placement, especially ću.

It can mean both, depending on context.

• kuhati = to cook
• sometimes also = to boil

In your sentence, kuhati juhu most naturally means to cook soup.

In other contexts:

• Kuham ručak. = I’m cooking lunch.
• Voda kuha. = The water is boiling.
• Kuham vodu. = I’m boiling water.

So the exact English translation depends on what is being cooked.

Because Croatian has no articles.

English uses:

• a
• an
• the

Croatian does not.

So:

• juha can mean soup or the soup
• djeca can mean children or the children

The exact meaning is understood from context.

That is why:

• juhu za djecu

can be translated as:

• soup for children
• the soup for the children
• soup for the children

depending on the situation.

No. You may also hear supa.

Both mean soup, but there are regional and stylistic differences:

• juha is standard and very common in Croatian
• supa is also used, but may sound more regional, colloquial, or associated with neighboring varieties depending on context

For a learner of standard Croatian, juha is the safest choice.

A simple approximate pronunciation is:

VE-che-ras chu KOO-ha-ti YOO-hoo za DYE-tsoo

A few details:

• č sounds roughly like ch in chocolate
• ć is softer than č, but many learners first approximate it with ch
• j is like English y
• dj in djecu is close to a soft dy sound

Word-by-word:

• Večeras = VE-che-ras
• ću = roughly chu
• kuhati = KOO-ha-ti
• juhu = YOO-hoo
• za = za
• djecu = roughly DYE-tsoo

Here is the breakdown:

• Večeras — adverb, so no case
• ću kuhati — future tense verb phrase
• juhu — accusative singular of juha
• za djecu — accusative plural after za

So the two nouns are both in the accusative, but for different reasons:

• juhu is accusative because it is the direct object
• djecu is accusative because it follows the preposition za

That is a very common thing in Croatian: the same case can appear for different grammatical reasons.