Ya sea en una revista o en un reportaje, mi hermana siempre busca información fiable antes de viajar.

It means whether ... or ..., be it ... or ..., or whether it is in ... or in ....

In this sentence, Ya sea en una revista o en un reportaje introduces two possible places/sources where the information might appear.

A very literal breakdown is:

• ya sea = whether it be / be it
• en una revista = in a magazine
• o en un reportaje = or in a report / feature article / news report

It is a common structure for presenting alternatives.

Because ya sea ... o ... normally uses the subjunctive.

Here, sea is the subjunctive form of ser. This structure is fixed in Spanish when you present alternatives in a general or non-specific way.

So Spanish says:

• Ya sea X o Y...

not normally:

• Ya es X o Y...

This is not about past vs present. It is about mood: Spanish uses the subjunctive because the speaker is not identifying one definite thing, but mentioning possible alternatives.

Because Ya sea en una revista o en un reportaje is an introductory phrase at the beginning of the sentence.

Spanish often separates this kind of opening phrase from the main clause with a comma:

• Ya sea en una revista o en un reportaje,
  mi hermana siempre busca...

The comma helps the reader see where the introductory part ends and the main statement begins.

Spanish can repeat the preposition before each option for clarity and balance.

So:

• en una revista o en un reportaje

sounds very natural.

You may sometimes see the preposition only once when the structure is very tight, but repeating it is especially common when listing alternatives. It makes the sentence clearer and more rhythmic.

Reportaje is a bit broader than the English word report.

In Spain, it often means:

• a feature article
• an in-depth news report
• a special report
• sometimes even a TV or radio documentary-style report

So in this sentence, reportaje is probably a journalistic piece that gives detailed information.

That is why magazine and reportaje fit together well: the sentence is talking about places where someone might read or watch useful travel information.

Yes, but fiable is especially common in Spain.

Both can mean reliable, but:

• fiable = the usual choice in Spain
• confiable = understood, but more common in many parts of Latin America

So for Spanish from Spain, información fiable sounds very natural.

Also, fiable agrees with información, but since it ends in -e, its form does not change for masculine/feminine singular.

Because Spanish often uses nouns like información without an article when speaking in a general sense.

So:

• busca información fiable = she looks for reliable information

This is like English, where you also usually would not say she looks for a reliable information.

If you added an article, it would sound more specific:

• busca la información fiable = she looks for the reliable information

That would suggest particular information already known in the context.

Because when the subject is the same, Spanish usually uses:

• antes de + infinitive

Here, the person who busca is also the person who viajar: mi hermana.

So:

• mi hermana siempre busca información fiable antes de viajar

means that she looks for information before she travels.

If the subject changed, Spanish would normally use:

• antes de que + subjunctive

For example:

• Mi hermana busca información fiable antes de que mis padres viajen.

That means the travelers are my parents, not my sister.

Also, antes de que viaja is incorrect. After antes de que, Spanish needs the subjunctive: viaje, viajen, etc.

Yes.

In antes de viajar, the infinitive viajar does not explicitly say the subject, but it is understood from the main clause. So the sentence means:

• My sister always looks for reliable information before traveling

with the understanding that she is the one traveling.

This is very common in Spanish.

Because the sentence describes a habit or something she generally does.

• mi hermana siempre busca... = my sister always looks for / always searches for...

The adverb siempre strongly suggests a repeated action, so the present tense is the normal choice.

It is not necessarily happening right now. It is a habitual present.

Yes. Spanish is fairly flexible with word order.

For example, these are also possible:

• Mi hermana siempre busca información fiable antes de viajar, ya sea en una revista o en un reportaje.
• Mi hermana, ya sea en una revista o en un reportaje, siempre busca información fiable antes de viajar.
  This one is less neutral and more marked stylistically.

The original version puts the alternatives first, which gives them emphasis.

Because subject + adverb + verb is the more natural neutral order here:

• mi hermana siempre busca

Spanish often places adverbs like siempre, nunca, ya, también, etc. before the main verb.

Other orders are possible for emphasis, but they sound less neutral:

• Siempre mi hermana busca... is unusual in normal speech.
• Mi hermana busca siempre... is possible, but often sounds a little less natural here than siempre busca.

So the original order is the most standard one.

In standard Spanish pronunciation, fiable is usually pronounced something like fya-ble, with ia forming a glide rather than being fully separated into two strong syllables.

Roughly:

• fia-ble

The stress falls on fia:

• FIA-ble

This can be tricky for English speakers, but the main point is that it does not sound like English fee-able.