Przy okienku urzędniczka daje mi potwierdzenie i kopię dokumentu.

Literally, okienko is a diminutive of okno (window), so it can mean little window.

But in places like offices, post offices, train stations, or government buildings, okienko very often means a service window or counter window. So in this sentence it does not sound especially cute or emotional; it is just a normal word for that kind of public-service window.

Because przy normally takes the locative case when it means at / by / next to.

So:

• dictionary form: okienko
• after przy: okienku

This is a very common pattern:

• przy stole = at the table
• przy drzwiach = by the door
• przy okienku = at the window/counter

Urzędniczka is in the nominative singular, because it is the subject of the sentence — the person doing the action.

It is the feminine form meaning female clerk / female office worker / female official.

Compare:

• urzędnik = male clerk/official
• urzędniczka = female clerk/official

So here urzędniczka daje... means the clerk gives...

Daje is the 3rd person singular present tense of dawać (to give, imperfective).

So it agrees with urzędniczka:

• ja daję = I give / I am giving
• ty dajesz = you give
• on/ona daje = he/she gives

Because Polish present-tense forms often cover both English simple present and present continuous, daje can mean either:

• gives
• is giving

depending on context.

Because daje comes from the imperfective verb dawać, while da comes from the perfective verb dać.

Very roughly:

• dawać / daje = giving, gives, is giving, repeated or ongoing action
• dać / da = a completed giving; in the present form it usually refers to the future: will give

So in a scene being described right now, daje is natural. If you said da, it would usually mean will give, not is giving.

Both mean to me, but mi is the short, unstressed form, and mnie is the fuller form.

In an ordinary neutral sentence, Polish usually prefers mi:

• daje mi dokument = she gives me the document

You use mnie more often when you want emphasis or contrast:

• Mnie daje dokument, a jemu nie. = She gives the document to me, but not to him.

Here there is no special emphasis, so mi is the normal choice.

Also, mi is in the dative case, because it is the indirect object: the person receiving something.

Both words are direct objects here, so both are in the accusative case. They just belong to different noun types, so they change differently.

• potwierdzenie is a neuter noun

  • nominative: potwierdzenie
  • accusative: potwierdzenie
    These two forms are the same.

• kopia is a feminine noun ending in -a

  • nominative: kopia
  • accusative: kopię

So:

• daje potwierdzenie
• daje kopię

This is very normal in Polish. Different noun genders and patterns give different accusative endings.

Because after kopia (copy), Polish normally uses the genitive for the thing being copied.

So:

• kopia dokumentu = copy of the document
• kopia paszportu = copy of the passport
• kopia umowy = copy of the contract

Here:

• kopię = accusative, because it is the direct object
• dokumentu = genitive, because it depends on kopia

This is a very common Polish structure: noun + genitive.

Most naturally, dokumentu goes directly with kopię, giving kopię dokumentu = a copy of the document.

So the sentence is most naturally understood as:

• the clerk gives me a confirmation
• and a copy of the document

In real context, the confirmation may also be related to the same document, but grammatically dokumentu is most directly attached to kopię.

Polish word order is more flexible than English because case endings show the grammatical roles.

This sentence starts with Przy okienku to set the scene:

• Przy okienku urzędniczka daje mi potwierdzenie i kopię dokumentu.

That feels like:

• At the counter, the clerk gives me a confirmation and a copy of the document.

You could change the order, but the emphasis would change a bit. For example:

• Urzędniczka przy okienku daje mi potwierdzenie i kopię dokumentu.
  More focus on the clerk.

• Urzędniczka daje mi przy okienku potwierdzenie i kopię dokumentu.
  Grammatically possible, but less natural in many contexts.

So the original word order is natural and neutral for describing a scene.

Because Polish does not have articles like English a/an and the.

So a noun like urzędniczka can mean:

• a clerk
• the clerk

depending on context.

The same is true for:

• potwierdzenie = a confirmation / the confirmation
• kopia dokumentu = a copy of the document / the copy of the document

Polish relies on context, word order, and shared knowledge instead of articles.

A rough English-friendly guide is:

urzędniczka ≈ oo-ZHEND-nich-ka

A few useful points:

• u = like oo in food
• rz = like the s in measure or zh
• ę before a consonant is usually pronounced with a nasal element, often roughly like en/em
• cz = like ch in church

So you do not need a perfect phonetic version at first; something close to oo-ZHEND-nich-ka will help you get started.