Zodra de website weer werkt, zal ik het document downloaden.

Zodra means as soon as.

It introduces something that will happen immediately after something else happens:

• Zodra de website weer werkt, zal ik het document downloaden.
• As soon as the website works again, I will download the document.

It is a common word for talking about one future action depending on another.

Because zodra introduces a subordinate clause. In Dutch, subordinate clauses usually send the conjugated verb to the end.

So:

• de website werkt weer = main clause word order
• zodra de website weer werkt = subordinate clause word order

That is why werkt comes last in that first part.

In Dutch main clauses, the conjugated verb normally comes in the second position.

Since the sentence starts with the subordinate clause Zodra de website weer werkt, that whole clause takes the first position. After that, the verb must come next:

• Zodra de website weer werkt, zal ik het document downloaden.

So the order becomes:

1. subordinate clause
2. conjugated verb: zal
3. subject: ik

This is called inversion.

If you started with the main clause, you would say:

• Ik zal het document downloaden zodra de website weer werkt.

This is the Dutch future tense:

• zal = will
• downloaden = download

Together, zal downloaden means will download.

So:

• ik zal downloaden = I will download

Dutch often forms the future with zullen + infinitive.

That said, Dutch also often uses the present tense for future meaning if the context is clear:

• Zodra de website weer werkt, download ik het document.

This can also be perfectly natural.

Dutch nouns take either de or het.

• website is a de-word → de website
• document is a het-word → het document

Unfortunately, this usually has to be learned with each noun. There are some patterns, but many nouns simply need to be memorized with their article.

A useful habit is to learn nouns as a unit:

• de website
• het document

not just website and document by themselves.

Here weer means again or back.

So de website werkt weer means:

• the website works again
• the website is working again
• the website is back up

It suggests that the website was not working before, but now it will return to normal.

Yes. Downloaden is a normal Dutch verb, borrowed from English but fully used in Dutch grammar.

Examples:

• ik download
• jij downloadt
• hij downloadt
• wij downloaden

In this sentence it stays in the infinitive form downloaden because it follows zal:

• zal ... downloaden

That is the normal pattern with auxiliaries in Dutch.

Sometimes, yes, but the meaning changes slightly.

• zodra = as soon as
• wanneer = when
• als = often if or sometimes when

In this sentence, zodra is best because it emphasizes immediately after the website starts working again.

Compare:

• Zodra de website weer werkt... = as soon as it works again
• Wanneer de website weer werkt... = when it works again
• Als de website weer werkt... = if/when it works again

So zodra is the most precise choice here.

Because the sentence starts with a subordinate clause:

• Zodra de website weer werkt, ...

In Dutch, a subordinate clause is usually separated from the main clause with a comma, especially when it comes first.

So the comma marks the boundary between:

• Zodra de website weer werkt
  and
• zal ik het document downloaden

Yes. A very common alternative is:

• Ik zal het document downloaden zodra de website weer werkt.

This means the same thing.

The difference is mainly in emphasis:

• Zodra de website weer werkt, ... puts focus on the timing first.
• Ik zal het document downloaden ... starts with the speaker and the action.

Both are correct.

Because in Dutch main clauses with an auxiliary like zal, the conjugated verb comes earlier and the main verb goes to the end.

So the basic structure is:

• zal
  • subject + object + infinitive

Here that gives:

• zal ik het document downloaden

Breaking it down:

• zal = will
• ik = I
• het document = the document
• downloaden = download

This is very typical Dutch word order with two verbs.