Il ladro confessa il furto.

Because il is the masculine singular definite article, meaning the.

In this sentence:

• il ladro = the thief
• il furto = the theft

Italian normally gives each noun its own article, so you do not use one il for both nouns.

Also, Italian uses articles more regularly than English, so leaving them out is usually not possible in a normal sentence like this.

Confessa is the third-person singular present indicative form of confessare.

It matches the subject il ladro, which is he / the thief.

A quick conjugation of the present tense:

• io confesso = I confess
• tu confessi = you confess
• lui/lei confessa = he/she confesses
• noi confessiamo = we confess
• voi confessate = you all confess
• loro confessano = they confess

So Il ladro confessa means the thief confesses.

That is a very common question for English speakers.

In Italian, confessare can be used directly with an object, without a preposition:

• confessare il furto
• confessare la verità
• confessare un delitto

So Italian says:

• Il ladro confessa il furto

where English more naturally often says:

• The thief confesses to the theft

This is a grammar difference between the two languages. Italian does not need a word corresponding to to here.

No. They are related, but not the same.

• confessare qualcosa = to confess / admit something
• confessarsi = to go to confession, or to confess oneself, usually in a religious sense

So in your sentence:

• Il ladro confessa il furto = the thief admits the theft

But:

• Il ladro si confessa would mean something more like the thief goes to confession or confesses himself in a religious context.

So you should not add si here unless you want to change the meaning.

Because this is the most neutral and standard Italian word order:

subject + verb + object

So:

• Il ladro = subject
• confessa = verb
• il furto = direct object

Italian can change word order for emphasis, style, or contrast, but the basic order is usually the clearest and most natural one.

For example, a different order might sound marked or literary unless the context strongly supports it.

Not in normal Italian.

Italian usually requires articles with singular countable nouns in a sentence like this. So:

• Il ladro confessa il furto is normal
• Ladro confessa furto sounds unnatural, incomplete, or like a headline fragment

English often allows article omission in headlines, but ordinary Italian does not work that way as freely.

Yes. Ladro is a masculine singular noun.

Here are the main forms:

• il ladro = the male thief
• la ladra = the female thief
• i ladri = the thieves, masculine or mixed group
• le ladre = the female thieves

So if the subject were feminine, you would say:

• La ladra confessa il furto

And if plural:

• I ladri confessano il furto

Furto is a masculine singular noun meaning theft.

In this sentence it is the direct object of the verb confessa.

That means it is the thing being confessed:

• subject: il ladro
• verb: confessa
• object: il furto

Its plural is:

• furti = thefts

So:

• il furto = the theft
• i furti = the thefts

It can depend on context.

Italian present tense often covers both:

• simple present: confesses
• present progressive sense: is confessing

So Il ladro confessa il furto could be understood as:

• The thief confesses the theft
• The thief is confessing the theft
• or, more naturally in English, The thief confesses to the theft / admits the theft

If Italian wants to emphasize the ongoing action, it can also use:

• Il ladro sta confessando il furto

But the simple present is very common and flexible.

Yes, the double ss matters in Italian pronunciation.

Confessa is pronounced with stress on the middle syllable:

• con-FES-sa

The ss is pronounced as a stronger, longer s sound than a single s.

A rough pronunciation guide:

• confessa ≈ kon-FESS-sa
• ladro ≈ LA-dro
• furto ≈ FOOR-to

A fuller approximation for the whole sentence is:

• eel LA-dro kon-FESS-sa eel FOOR-to

A few useful notes:

• il sounds more like eel than English ill
• r in Italian is usually tapped or lightly rolled
• u in furto is a pure oo sound, not the English uh

Usually, yes.

The definite article il often suggests that the thief and the theft are identifiable from context:

• a thief already mentioned
• a theft already known to the speaker and listener

So the sentence most naturally sounds like:

• the thief confesses the theft

However, like English the, Italian articles can sometimes also be used in broader or more general ways depending on context. In an isolated sentence, though, most learners should read this as referring to a specific thief and a specific theft.