Quero renovar a Carteira Nacional de Habilitação; está vencida.

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

• Quero = I want
• The -o ending shows it is eu

So both of these are correct:

• Quero renovar...
• Eu quero renovar...

The version without eu sounds very natural and is extremely common in Brazilian Portuguese.

After querer when you mean want to do something, Portuguese uses the infinitive.

• quero renovar = I want to renew
• quero viajar = I want to travel
• quero comer = I want to eat

So:

• quero = conjugated verb
• renovar = infinitive that explains what you want to do

Using renovo here would be wrong, because renovo is a conjugated form meaning I renew.

This is the full official Brazilian term for a driver’s license. It is often abbreviated as CNH.

Word by word:

• carteira = card, booklet, wallet-type document
• nacional = national
• de habilitação = of authorization/licensing

In everyday Brazilian Portuguese, people often just say:

• a CNH
• a carteira
• a carteira de motorista (very common and easy to understand)

It is capitalized here because it is being treated as the official name of a specific document, similar to a formal title.

So you may see:

• Carteira Nacional de Habilitação when referring to the official document name
• carteira de motorista in more everyday, non-official usage

In normal writing, capitalization may vary depending on style, but using capitals for the official full name is very natural.

Because carteira is a feminine noun, and Portuguese usually uses the definite article with nouns more often than English does.

• a carteira
• a CNH

So:

• renovar a Carteira Nacional de Habilitação = renew the driver’s license

In English, you might say renew my driver’s license or renew the driver’s license, but Portuguese very naturally uses the article here.

It can, but it does not have to.

Portuguese often leaves out possessives like my, your, his, etc. when the context already makes ownership clear.

So all of these are possible:

• Quero renovar a Carteira Nacional de Habilitação.
• Quero renovar minha Carteira Nacional de Habilitação.
• Quero renovar a minha CNH.

The version without minha is completely natural, especially when it is obvious that you mean your own license.

Because estar is normally used for a temporary state or condition, and vencida here means expired or out of date.

• está vencida = it is expired
• está aberta = it is open
• está fechada = it is closed

Using ser here would sound wrong in normal speech.

Also, vencida is a past participle/adjectival form from vencer, and with documents or deadlines it means expired.

Because vencida agrees with Carteira, which is feminine singular.

• a carteira → feminine singular
• therefore: vencida

Examples:

• O passaporte está vencido.
  Passport is masculine, so vencido

• A carteira está vencida.
  License/wallet is feminine, so vencida

This adjective agreement is very important in Portuguese.

Literally, vencer can mean things like to defeat, to overcome, or to expire, depending on context.

With documents, bills, deadlines, and dates, vencido/vencida usually means:

• expired
• past due
• no longer valid

So for a driver’s license:

• A CNH está vencida = The license has expired / is expired

For a bill:

• A conta está vencida = The bill is overdue

Yes, the semicolon is fine in writing, especially to connect two closely related ideas:

• Quero renovar a Carteira Nacional de Habilitação; está vencida.

But in everyday speech and ordinary writing, many Brazilians would more often say:

• Quero renovar a Carteira Nacional de Habilitação porque está vencida.
• Quero renovar a minha CNH, porque ela está vencida.
• Minha CNH está vencida, então quero renovar.

So the semicolon version is correct, but other versions may sound more conversational.

Portuguese often omits a subject pronoun when it is understood from context.

Here, está vencida clearly refers back to a Carteira Nacional de Habilitação.

So both are possible:

• ... está vencida.
• ... ela está vencida.

The version without ela is very natural and avoids repetition.

Yes. Carteira de motorista is a very common everyday way to say driver’s license.

Compare:

• Carteira Nacional de Habilitação = official/formal term
• carteira de motorista = common everyday term

You could say:

• Quero renovar minha carteira de motorista; está vencida.

In Brazil, people will also very often say simply:

• Quero renovar minha CNH.

In this context, habilitação means authorization/licensing to drive. It is part of the official name of the license.

More generally, habilitação can refer to qualification, certification, or legal authorization to do something. But in Brazil, when people mention a habilitação, it very often relates to driving.

So:

• tirar habilitação = to get a driver’s license
• renovar a habilitação = to renew a driver’s license

Sometimes, but renovar is the standard and best choice for documents like licenses, passports, registrations, and subscriptions.

• renovar a CNH = renew the license
• renovar o passaporte = renew the passport

You might also hear verbs like atualizar in other contexts, but for a document that has expired and needs a new period of validity, renovar is the normal word.

A very natural everyday version would be:

• Quero renovar minha CNH. Ela está vencida.

Other common natural versions:

• Preciso renovar minha CNH. Está vencida.
• Minha CNH venceu, então preciso renovar.

Your original sentence is correct, but in conversation many speakers would use CNH instead of the full official name.