Ne znam kuda ide pošiljka.

Because kuda asks about direction or route, not just location.

• gde = where in the sense of at what place
• kuda = where to / which way / along what route

In Ne znam kuda ide pošiljka, the idea is not Where is the package right now? but What way is it going? / Where is it headed?

So kuda fits better with a verb of movement like ide.

Kuda is an interrogative/relative adverb used with movement. It can mean:

• where to
• which way
• along what route

In indirect questions, as in this sentence, it often means something like where it is going or which route it is taking.

So Ne znam kuda ide pošiljka is literally close to:

• I don't know where the package is going
• I don't know which way the package is going

Yes, ide literally means goes, from the verb ići = to go. But in Serbian, just like in English, verbs of motion are often used for things that are being transported.

So a package can ići:

• through the mail system
• to a destination
• by a certain route

This is completely natural. English also says things like:

• The package is going to Germany
• Where is the shipment going?

So ide here is normal and idiomatic.

Ide is the 3rd person singular present tense of ići (to go).

Here is the present tense:

• ja idem = I go / I am going
• ti ideš = you go
• on/ona/ono ide = he/she/it goes
• mi idemo = we go
• vi idete = you go
• oni/one/ona idu = they go

Because pošiljka is singular, the verb is ide.

Pošiljka is in the nominative singular because it is the grammatical subject of the sentence.

• pošiljka = shipment / package
• It is a feminine noun
• Since it is the thing that ide, it stays in the nominative

So:

• Pošiljka ide. = The package is going.

Serbian has no articles like a or the.

So pošiljka can mean:

• a package
• the package
• shipment
• the shipment

Which one is intended depends on context. In this sentence, English will often use the package or the shipment, but Serbian simply says pošiljka.

Because kuda ide pošiljka is an indirect question: I don't know where the package is going.

In Serbian, indirect questions often use question words directly:

• Ne znam gde je. = I don't know where he is.
• Ne znam kada dolazi. = I don't know when he is coming.
• Ne znam kuda ide pošiljka. = I don't know where the package is going.

You usually do not use da before this kind of clause.

The given order is the most neutral and natural:

• Ne znam kuda ide pošiljka.

But Serbian word order is somewhat flexible. For example, you might also hear:

• Ne znam kuda pošiljka ide.

That is possible, but it may sound slightly more marked or stylistically different depending on context. For a learner, the original order is the best one to use first.

You might hear it in casual speech, and people would probably understand you, but kuda is more precise and standard here.

• gde ide can sound like where is it going
• kuda ide clearly focuses on direction/route

With movement, especially when talking about path or destination, kuda is the better choice.

Both can refer to something being sent, but they are not exactly the same.

• paket = package / parcel as a physical box or parcel
• pošiljka = shipment / consignment / mailed item

Pošiljka is a bit broader and often used in postal, delivery, or tracking contexts. A pošiljka could be a paket, a letter, or some other sent item.

So in a tracking-style sentence, pošiljka is very natural.

It is pronounced approximately like po-sheel-yka, but with Serbian sounds:

• po
• šilj
• ka

A few helpful notes:

• š sounds like English sh
• lj is a special Serbian sound, something like the lli in million for many English speakers
• stress can vary by dialect and speaking style, but learners usually do fine focusing on the consonants first

So a rough English-friendly approximation is po-SHEEL-yka.

Yes. That is one of the useful things about kuda.

Depending on context, Ne znam kuda ide pošiljka can suggest:

• I don't know where the package is going
• I don't know which way the package is going
• I don't know what route the package is taking

So kuda can cover both destination and route/direction, depending on the situation.

Yes, this is the normal Serbian expression.

• znam = I know
• ne znam = I don't know

The negation ne is written separately from the verb:

• Ne znam
• Ne idem
• Ne mogu

So Ne znam kuda ide pošiljka is structurally very straightforward:

• Ne znam = I don't know
• kuda ide pošiljka = where/which way the package is going