Eu vou pagar o aluguel pela internet agora.

Vou pagar is the very common ir + infinitive future, literally I am going to pay.

In Brazilian Portuguese, this structure is often more natural in everyday speech than the simple future form pagarei.

• Eu vou pagar o aluguel agora = I’m going to pay the rent now
• Eu pagarei o aluguel agora = grammatically correct, but more formal or less common in casual conversation

So for normal spoken Brazilian Portuguese, vou pagar is usually the best choice.

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

So these both work:

• Eu vou pagar o aluguel pela internet agora.
• Vou pagar o aluguel pela internet agora.

Both mean the same thing. Including Eu can add emphasis, contrast, or clarity.

For example:

• Eu vou pagar o aluguel, não você.
  I’m going to pay the rent, not you.

Because aluguel is a masculine noun in Portuguese, and in this sentence it is being used with the definite article o, meaning the.

• o aluguel = the rent

In Portuguese, using the article is often more natural than in English. English says pay rent or pay the rent, but Portuguese very often uses the article:

• pagar o aluguel = pay the rent

Saying just pagar aluguel is possible in some contexts, but pagar o aluguel sounds more complete and natural when talking about a specific rent payment.

In Brazilian Portuguese, aluguel usually means rent or rental payment, especially for a house or apartment.

In this sentence:

• pagar o aluguel = to pay the rent

It can also refer more generally to something rented or the rental cost, depending on context, but rent is the most likely meaning here.

Pela is a contraction of:

• por + a = pela

In this sentence, pela internet means something like:

• through the internet
• over the internet
• more naturally in English: online

So:

• pagar o aluguel pela internet = pay the rent online / over the internet

This use of por often expresses the means or method used to do something.

Both can appear in Portuguese, but they suggest slightly different ideas.

• pela internet focuses on the means/method: through the internet, online
• na internet literally means on the internet, and is often used when talking about location or where something is found

For paying a bill or rent, pela internet is very natural because the internet is the method used to make the payment.

Examples:

• Vou pagar pela internet. = I’m going to pay online.
• Vi isso na internet. = I saw that on the internet.

Yes, agora is perfectly natural at the end.

• Eu vou pagar o aluguel pela internet agora.

But Portuguese allows some flexibility. You could also say:

• Agora eu vou pagar o aluguel pela internet.
• Eu vou pagar agora o aluguel pela internet.
  This is possible, but less natural in everyday speech.

The version with agora at the end sounds very normal and conversational.

Yes, it sounds natural.

A Brazilian speaker would easily say:

• Vou pagar o aluguel pela internet agora.

Other natural variations include:

• Vou pagar o aluguel online agora.
• Agora vou pagar o aluguel pela internet.

Using online is also very common in Brazil, especially in informal speech.

No. Nothing changes here.

• Eu vou pagar o aluguel pela internet agora.

This sentence is the same whether the speaker is male or female, because none of the words in it need to agree with the speaker’s gender.

In Brazilian Portuguese, aluguel is approximately pronounced ah-loo-GHEL.

A few helpful notes:

• the stress falls on the last syllable: -guel
• the lh sound does not appear here; the word is spelled aluguel, not aluguelh
• the final l in Brazilian Portuguese often sounds like a soft w sound in many accents

A rough English-friendly approximation is:

• ah-loo-GHEW

But the exact sound depends on accent.

Yes. In Brazil, online is very common and sounds natural.

So these are both fine:

• Eu vou pagar o aluguel pela internet agora.
• Eu vou pagar o aluguel online agora.

Pela internet sounds slightly more literally Portuguese, while online is extremely common in modern everyday speech.

In more formal Portuguese, you could say:

• Eu vou pagá-lo pela internet agora.

Here, pagá-lo means pay it.

Why does pagar + o become pagá-lo?

• the direct object pronoun for a masculine singular noun is o
• after an infinitive ending in -r, the r drops and -lo is attached
• pagar + o → pagá-lo

That said, in everyday spoken Brazilian Portuguese, people often avoid this structure and just keep the noun:

• Vou pagar o aluguel agora.

That is usually the most natural choice in conversation.