Le tableau des départs indique l’annulation.

Not here. Tableau can mean several things in French, including painting, chart, board, or display depending on context.

In Le tableau des départs, it means the departure board or departures display, like the screen or board in a station or airport.

So this is not about a painting at all.

Here, des is the contraction of de + les.

• le tableau = the board
• des départs = of the departures

So le tableau des départs literally means the board of the departures, which in natural English becomes the departure board.

This is a very common French structure:

• le tableau des arrivées = the arrivals board
• la porte de la salle = the door of the room
• le nom des étudiants = the name of the students

Because a departures board shows many departures, not just one.

• un départ = a departure
• des départs = departures

So le tableau des départs is the board listing multiple departing trains, flights, etc.

Because the subject is singular: Le tableau des départs.

The main noun is tableau, which is singular:

• Le tableau ... indique = The board indicates

Even though départs is plural, it is inside the phrase des départs and is not the subject of the verb.

So the verb agrees with tableau, not with départs.

Indique is the he/she/it form of indiquer.

Here it means something like:

• indicates
• shows
• states

So Le tableau des départs indique l’annulation means the board shows or indicates that there is a cancellation.

In everyday English, shows may sound more natural, but indicates is a very good direct match.

Because French usually drops the vowel of le or la before a word beginning with a vowel or silent h.

So:

• la annulation becomes l’annulation

This is called elision.

Other examples:

• l’hôtel
• l’école
• l’arrivée

Annulation is a noun. It means cancellation.

• l’annulation = the cancellation

Annulé is usually a past participle or adjective meaning cancelled.

For example:

• Le vol est annulé. = The flight is cancelled.
• Le tableau indique l’annulation du vol. = The board indicates the cancellation of the flight.

So in your sentence, French uses the noun annulation, not the adjective annulé.

French can leave that unstated if the context makes it clear.

Le tableau des départs indique l’annulation means the board indicates a cancellation or the cancellation, and the exact train/flight may be understood from the situation.

A fuller version could be:

• Le tableau des départs indique l’annulation du train.
• Le tableau des départs indique l’annulation du vol.

But the shorter sentence is still natural if the context is obvious.

Yes, very similar.

French:

• Le tableau des départs = the departure board
• indique = indicates
• l’annulation = the cancellation

So the structure is:

Subject + verb + object

That makes this sentence fairly straightforward for an English speaker.

A simple pronunciation guide is:

luh ta-bloh day day-par an-deek la-nu-la-syon

A few useful points:

• tableau sounds roughly like ta-bloh
• des here sounds like day
• départs has a silent final s
• indique sounds like an-deek
• l’annulation links smoothly after indique

In careful IPA, it is approximately:

lə tablo de depa ɛ̃dik lanylasjɔ̃

Sometimes, yes, depending on the situation.

For an airport or station board, tableau is very common and natural. It suggests a board, sign, or display listing information.

You may also hear words like:

• panneau = sign / board
• écran = screen

But le tableau des départs is a standard and useful phrase to learn for transport contexts.