Depois que a garçonete servir a sobremesa, nós vamos pagar e ir embora.

Because this clause refers to a future action: first the waitress will serve dessert, and only after that will we pay and leave.

In Portuguese, conjunctions like depois que, quando, assim que, and se often take the future subjunctive when they refer to a future event. So:

• Depois que a garçonete servir a sobremesa... = after the waitress serves the dessert...
• not serve in standard grammar for this meaning
• not usually servirá after depois que

So servir here is the correct future-subjunctive form.

Functionally, no. It is the future subjunctive, even though it looks identical to the infinitive.

For many verbs, the future subjunctive and the infinitive have the same form in the 1st and 3rd person singular. That is why this can be confusing.

Compare:

• infinitive: servir
• future subjunctive, eu/ele/ela/você: servir
• future subjunctive, nós: servirmos

If the sentence had nós, you could see the difference more clearly:

• Depois que nós servirmos a sobremesa...

So in your sentence, servir is not just a dictionary form sitting there; it is a conjugated verb form.

Depois que introduces a full clause with its own subject and verb:

• Depois que a garçonete servir a sobremesa...

Here, the clause has:

• subject: a garçonete
• verb: servir

By contrast, depois de is usually followed by a noun or an infinitive phrase:

• depois do jantar
• depois de comer

You can also say:

• Depois de a garçonete servir a sobremesa...

That is grammatical, but depois que is often simpler and very natural in Brazilian Portuguese.

A useful extra note: in everyday speech, many Brazilians also say depois da garçonete servir, but in more careful grammar, depois de a garçonete servir is preferred.

Because ir + infinitive is a very common way to talk about the future in Brazilian Portuguese.

So:

• nós vamos pagar = we are going to pay / we will pay

This is usually more natural in everyday speech than the simple future:

• nós pagaremos

Both are correct, but they feel a bit different:

• vamos pagar = very common, conversational
• pagaremos = more formal, more written, or more emphatic

Yes. Portuguese often drops subject pronouns when the verb already makes the subject clear.

So these are both correct:

• Nós vamos pagar e ir embora.
• Vamos pagar e ir embora.

Including nós can add emphasis, contrast, or clarity, but it is not required.

Both of them are just the feminine singular definite article, meaning the.

• a garçonete = the waitress
• a sobremesa = the dessert

So neither a is a pronoun here, and neither is a special marker like Spanish personal a. They are simply articles matching feminine nouns.

Ir embora is a very common expression meaning to leave, to go away, or to head off.

So:

• pagar e ir embora = pay and leave

Word by word, ir means to go and embora originally has an idea like away, but together the phrase is best learned as a unit:

• ir embora = leave

It is one of those expressions that sounds much more natural if you treat it as a chunk.

Because vamos can govern both infinitives:

• pagar
• ir embora

So the structure is basically:

• nós vamos [pagar] e [ir embora]

This is very natural, just like English can say we’re going to pay and leave.

You could repeat vamos, but it is less smooth:

• Nós vamos pagar e vamos embora

That version is possible, but it changes the rhythm and can sound more segmented. The original sentence is cleaner.

Because after the auxiliary vamos, the following verbs stay in the infinitive:

• vamos pagar
• vamos ir embora

When two verbs are coordinated, both stay in that basic infinitive form:

• vamos pagar e ir embora

Irmos is a personal infinitive, and that is not what you use after vamos here.

So:

• nós vamos pagar e ir embora = correct
• nós vamos pagar e irmos embora = not correct in this structure

Yes, it is standard and natural here.

The sentence begins with a subordinate time clause:

• Depois que a garçonete servir a sobremesa, ...

When that kind of clause comes first, Portuguese normally uses a comma before the main clause:

• Depois que a garçonete servir a sobremesa, nós vamos pagar e ir embora.

If you put the main clause first, the comma is usually not needed:

• Nós vamos pagar e ir embora depois que a garçonete servir a sobremesa.

Sometimes yes, but the meaning changes slightly.

• Depois que a garçonete servir a sobremesa... = after the waitress serves the dessert
• Quando a garçonete servir a sobremesa... = when the waitress serves the dessert

Both can work in a future context, and both take the future subjunctive here:

• depois que ... servir
• quando ... servir

But depois que clearly emphasizes that one action happens after the other. Quando is a bit broader and simply places the action at that time.

Yes, garçonete means waitress, and garçom means waiter.

That said, in modern Brazilian Portuguese, many people also use more neutral or job-specific terms depending on the context, but garçonete is a standard, understandable word.

In this sentence, it is simply the feminine noun that matches a female server.