Antigo ou não, este livro ainda me ajuda a estudar.

This opening means something like Old or not or Whether it is old or not.

It is a concessive expression: the speaker is saying that the book’s age does not change the main point. In other words:

Even if it’s old, this book still helps me study.

Starting with Antigo ou não gives the sentence a slightly more emphatic or contrastive feel.

Because antigo is describing livro, which is:

• masculine
• singular

So the adjective must match it: antigo.

Portuguese often allows this kind of shortened structure where the adjective appears first and the noun comes later:

Antigo ou não, este livro...

It is understood as referring to este livro.

Both can relate to age, but they are not always the same.

• antigo = old, antique, from an earlier time
• velho = old, but often more like worn out, aged, or old in a more physical sense

For a book, antigo often sounds more neutral or respectful, especially if you are talking about its age rather than its bad condition.

So Antigo ou não here focuses on the fact that the book may be old, not necessarily damaged or useless.

Este livro means this book.

In European Portuguese, demonstratives are traditionally:

• este = this, near the speaker
• esse = that, near the listener
• aquele = that over there, farther away from both

So este livro is the natural choice for this book.

In real usage, especially in speech, the system can be a bit looser, but for a learner, este = this is a good rule here.

Here ainda means still.

So:

este livro ainda me ajuda a estudar = this book still helps me study

It shows continuation: the book continues to be useful now, even if it is old.

Be careful, because ainda can also mean other things in different contexts, such as yet or even, but here still is the right meaning.

This is about pronoun placement.

In European Portuguese, object pronouns often come after the verb in affirmative main clauses:

• ajuda-me = helps me

But some words attract the pronoun before the verb, and ainda is one of those common triggers. That is why:

• ainda me ajuda is natural here

So in this sentence, me comes before ajuda because of ainda.

Here me means me.

It is the object of ajudar:

• ajudar alguém = to help someone

So:

• ajuda-me
• me ajuda

both mean helps me

This is not the same as verbs that require a before a person, such as telefonar a alguém. With ajudar, the person being helped is normally a direct object.

Because the usual pattern is:

ajudar alguém a fazer alguma coisa = to help someone do something

So:

ajuda-me a estudar = helps me study

The a links ajudar to the infinitive estudar.

This is a very common structure in Portuguese:

• ajudar a compreender
• ajudar a trabalhar
• ajudar a aprender

Yes, you can think of it as a shortened version of a fuller idea such as:

• Seja antigo ou não...
• Quer seja antigo ou não...
• Sendo antigo ou não...

But Portuguese often prefers the shorter, more natural form:

Antigo ou não, este livro ainda me ajuda a estudar.

So there is an implied idea like whether it is old or not, even though no extra verb is stated.

Yes. That is a very close literal translation and it works well in English.

A slightly less literal but very natural English version would be:

• Whether it’s old or not, this book still helps me study.
• Even though it’s old, this book still helps me study. — but this version assumes it really is old

The Portuguese original keeps that open: maybe it is old, maybe not; either way, it is still useful.