A ilha fica longe.

Because ilha is a feminine noun in Portuguese.

• o = the for masculine singular nouns
• a = the for feminine singular nouns

So:

• o carro = the car
• a ilha = the island

This is something you usually just have to learn with each noun.

In Brazilian Portuguese, ilha is pronounced roughly like EEL-ya.

A few important points:

• i sounds like ee
• lh is a special Portuguese sound, similar to the lli in some pronunciations of million, but cleaner and more distinct
• the h by itself is silent in Portuguese, but in lh it helps form that special consonant sound
• the final a is usually a light ah

So ilha is not pronounced like English ill-ha.

Here, fica means something like:

• is located
• is situated
• ends up being
• in natural English, often just is

So A ilha fica longe literally feels like The island is located far away.

In Portuguese, ficar is very commonly used to talk about where something is.

For example:

• O banco fica no centro. = The bank is downtown.
• A praia fica perto. = The beach is nearby.

Because ficar is very natural when talking about location.

If you say A ilha é longe, that sounds wrong or very unnatural in Portuguese. Portuguese normally uses:

• ficar longe
• or sometimes ser distante

So:

• A ilha fica longe. = natural
• A ilha é distante. = also possible, a bit more formal
• A ilha é longe. = not standard

This is one of those cases where Portuguese does not match English word-for-word.

Fica is the third-person singular present indicative form of ficar.

The subject is a ilha, which is singular, so the verb is singular too.

Present tense of ficar:

• eu fico
• você / ele / ela fica
• nós ficamos
• vocês / eles / elas ficam

So in A ilha fica longe, fica matches a ilha.

Longe means far or far away.

In this sentence, it describes distance. It often appears with verbs like:

• ficar
• estar
• morar

Examples:

• Moro longe. = I live far away.
• O hotel fica longe. = The hotel is far away.

You will also often see longe de when the sentence says far from something:

• A ilha fica longe da cidade. = The island is far from the city.

Normally, the most neutral order is:

• A ilha fica longe.

That is the standard word order.

You might move things around in special contexts, but for a learner, the safest pattern is:

subject + verb + longe

Examples:

• A escola fica longe.
• Minha casa fica longe.

So yes, Portuguese can sometimes vary word order for emphasis, but this sentence is already in the most natural basic order.

Usually, no.

In normal Portuguese, a countable singular noun like ilha usually needs an article or some other determiner:

• A ilha fica longe.
• Essa ilha fica longe.
• Uma ilha fica longe.

Just Ilha fica longe sounds incomplete in ordinary speech.

It means the island.

That is because a here is the definite article, meaning the.

Compare:

• a ilha = the island
• uma ilha = an island

So if you wanted to say An island is far away, you would say:

• Uma ilha fica longe.

It works in Brazilian Portuguese and is also understandable and natural in Portuguese more generally.

The biggest difference would usually be pronunciation, not the grammar of this sentence.

So a Brazilian learner can safely use:

• A ilha fica longe.

That said, accent and rhythm will differ between Brazil and Portugal.

Yes, A ilha está longe is possible and understandable.

But there is a slight nuance:

• fica longe often sounds like is located far away
• está longe can sound more like is far away in the current situation or from a certain reference point

In many everyday contexts, both work. Still, for talking about where a place is located, fica is extremely common and very natural in Brazilian Portuguese.

Because Portuguese does not need a separate word there.

English often says far away, but Portuguese can simply say:

• longe

So:

• A ilha fica longe. = The island is far away.

The idea of away is already built into longe in this kind of sentence.