Eu vou arquivar a guia de pagamento.

Yes. In Brazilian Portuguese, eu can often be omitted because vou already shows that the subject is I.

So both are natural:

• Eu vou arquivar a guia de pagamento.
• Vou arquivar a guia de pagamento.

Including eu can add emphasis, clarity, or contrast, especially if you want to stress I rather than someone else.

Vou arquivar is the very common future structure ir + infinitive, which means am going to file.

• vou = I go / I am going
• arquivar = to file / to archive

So eu vou arquivar means I am going to file.

This is one of the most common ways to talk about the near future in Portuguese.

Because after vou, Portuguese uses the infinitive.

• vou arquivar = I am going to file
• arquivo = I file or file/archive as a noun in some contexts

Compare:

• Eu arquivo a guia de pagamento. = I file the payment slip.
• Eu vou arquivar a guia de pagamento. = I am going to file the payment slip.

So vou needs the verb in its base form: arquivar.

Arquivar means to file, to archive, or to put into records.

It can be used for:

• physical documents in a folder or cabinet
• digital documents in a computer system
• official records

So this sentence could refer to filing a paper document or saving/organizing it in an administrative system, depending on context.

Guia de pagamento usually refers to a payment form, payment slip, or payment document used to make or record a payment.

The exact translation depends on context, because guia can have different administrative meanings in Portuguese. In bureaucratic or financial contexts, it often means a document related to payment.

It is not usually guide in the English sense here.

Because guia in this sentence is a feminine noun meaning a document/form.

So it takes the feminine article:

• a guia

Be aware that guia can sometimes be masculine or feminine depending on meaning in Portuguese, but in the sense of a document like this, a guia is the normal form.

De pagamento means of payment or more naturally in English, payment as a modifier.

It specifies what kind of guia it is:

• guia = form/document/slip
• guia de pagamento = payment form/slip/document

This is very common in Portuguese: noun + de + noun.

Similar patterns:

• comprovante de residência = proof of address
• nota de pagamento = payment note/document
• data de vencimento = due date

Yes, it is natural, especially in administrative, office, accounting, or bureaucratic contexts.

It sounds like something someone might say in a workplace when dealing with paperwork:

• Eu vou arquivar a guia de pagamento.

In casual everyday conversation, someone might also choose a different verb depending on the situation, such as:

• guardar = to keep/put away
• salvar = to save
• separar = to set aside

But arquivar is perfectly natural when you specifically mean filing a document.

Yes. Portuguese allows some flexibility.

These are all possible, depending on emphasis:

• Eu vou arquivar a guia de pagamento.
• Vou arquivar a guia de pagamento.
• A guia de pagamento, eu vou arquivar. ← more marked, used for emphasis

The most neutral versions are the first two.

Yes. In many contexts, that is a perfectly good English translation.

Although vou arquivar literally matches am going to file, English may use either:

• I am going to file the payment slip
• I will file the payment slip

The Portuguese structure here is specifically ir + infinitive, but the best English translation can vary depending on style and context.

In Brazilian Portuguese, guia is pronounced roughly like GHEE-ah, with two syllables:

• gui-a

A helpful approximation is GEE-ah, though the exact sound of gui in Portuguese is a little different from English.

And arquivar is roughly:

• ar-kee-VAR

The stress is on the last syllable: var.

Sometimes yes, but the meaning changes slightly.

• arquivar = to file/archive formally, often as part of record-keeping
• guardar = to keep/put away/store

So:

• Vou arquivar a guia de pagamento. = I’m going to file the payment document.
• Vou guardar a guia de pagamento. = I’m going to keep/put away the payment document.

If you mean organizing it as part of paperwork or records, arquivar is the better choice.