Temel yaşam desteği ilk yardım eğitiminde gösteriliyor.

A natural breakdown is:

• temel = basic, fundamental
• yaşam = life, living
• desteği = support
  Together, yaşam desteği means life support
• ilk yardım = first aid
• eğitiminde = in the training / in its training context
• gösteriliyor = is being shown / is demonstrated

So the sentence means something like:

• Basic life support is demonstrated in first aid training.

In Turkish, multi-word noun phrases are very common, so several words work together as one unit.

Because yaşam desteği is a noun compound in Turkish.

The pattern is often:

• Noun + Noun-(s)I

So:

• yaşam = life
• destek = support
• yaşam desteği = life support

That final -i / -ı / -u / -ü on the second noun is very common in Turkish compounds. It does not mean direct object here. It is part of the compound structure.

Other similar examples:

• çocuk doktoru = pediatrician / children’s doctor
• ev kapısı = house door / front door of a house
• ilk yardım eğitimi = first aid training

So desteği here is not random—it is how Turkish builds the phrase life support.

No—here it is not the accusative.

In yaşam desteği, the -i is the compound/possessive ending used in a noun compound. This is a very common point of confusion for English speakers, because the ending can look like the accusative.

Compare:

• yaşam desteği = life support
  Here -i is part of the noun phrase.
• yaşam desteğini = the life support
  Here -ni includes the accusative on top of the compound form.

So in your sentence:

• Temel yaşam desteği = basic life support

This whole phrase is the subject of the passive sentence, not a direct object.

It comes from the noun phrase:

• ilk yardım eğitimi = first aid training

Then Turkish adds the locative ending -de / -da to mean in / at:

• ilk yardım eğitiminde = in first aid training

So the structure is:

• ilk yardım = first aid
• eğitim-i = its training / training of first aid → first aid training
• eğitim-in-de = in the training

A more literal breakdown is:

• eğitim = training
• -i = compound/possessive ending
• -nde = in/on/at it

So ilk yardım eğitiminde means in first aid training or during first aid training.

Because the base phrase is not just eğitim. It is ilk yardım eğitimi.

Once the noun has that compound/possessive ending -i, and you add a case ending like -de, Turkish usually inserts a buffer -n-:

• eğitimi
  • -de → eğitiminde

So this is the pattern:

• eğitim = training
• eğitimi = its training / training of X
• eğitiminde = in its training / in the X training

That -n- is there for pronunciation and grammar; it often appears after possessive endings before case suffixes.

Gösteriliyor is built from the verb göstermek, which means to show or to demonstrate.

It contains:

• göster- = show
• -il- = passive
• -iyor = present continuous / current ongoing form

So:

• gösteriliyor = is being shown, is shown, or is being demonstrated

In many contexts, English may translate this passive present form more naturally as:

• is demonstrated
• is shown
• is being shown

All of those can fit, depending on context.

Turkish often uses the passive when the person doing the action is not important, unknown, or obvious from context.

So instead of saying:

• An instructor demonstrates basic life support in first aid training

Turkish can naturally say:

• Temel yaşam desteği ilk yardım eğitiminde gösteriliyor
• Basic life support is demonstrated in first aid training

This keeps the focus on basic life support, not on the instructor.

That is very normal in explanations, textbooks, training descriptions, signs, and formal language.

It can do either, depending on context.

In Turkish, -iyor often means:

1. an action happening now
   
   • is being shown right now
2. a regular or general situation
   
   • is shown / is demonstrated

In this sentence, without extra context, many learners should understand it as a general statement:

• Basic life support is demonstrated in first aid training.

So even though the form looks like English present continuous, Turkish often uses it more broadly.

Because temel is an adjective meaning basic, and Turkish adjectives come before the noun they describe.

So:

• temel yaşam desteği = basic life support

Here temel describes the whole noun phrase yaşam desteği.

This is similar to English word order:

• basic life support

So that part is actually quite straightforward for English speakers.

Yes. Turkish word order is flexible, although some orders sound more neutral than others.

Your sentence:

• Temel yaşam desteği ilk yardım eğitiminde gösteriliyor.

A very natural alternative is:

• İlk yardım eğitiminde temel yaşam desteği gösteriliyor.

Both mean essentially the same thing:

• Basic life support is demonstrated in first aid training.

The difference is mainly focus:

• starting with Temel yaşam desteği emphasizes what is demonstrated
• starting with İlk yardım eğitiminde emphasizes where/when it happens

Turkish often moves elements around for topic and emphasis.

Because Turkish does not have articles like English a/an and the.

So a phrase like:

• temel yaşam desteği

can mean:

• basic life support
• the basic life support

depending on context.

Likewise:

• ilk yardım eğitiminde = in first aid training / in the first aid training

Context usually makes the meaning clear.

This is one reason Turkish can feel more compact than English.

It is close, but gösteriliyor specifically means is shown / is demonstrated.

If you want to say is taught, Turkish would more naturally use:

• öğretiliyor = is taught

So:

• Temel yaşam desteği ilk yardım eğitiminde öğretiliyor.
• Basic life support is taught in first aid training.

Your original sentence suggests demonstration or presentation, not necessarily full teaching.

You could say something like:

• İlk yardım eğitiminde eğitmen temel yaşam desteğini gösteriyor.
• In first aid training, the instructor demonstrates basic life support.

Notice an important change:

• In the passive sentence: temel yaşam desteği is the subject
• In the active sentence: temel yaşam desteğini becomes the direct object, so it takes the accusative

Compare:

• Temel yaşam desteği ... gösteriliyor.
  Basic life support ... is demonstrated.
• Eğitmen temel yaşam desteğini gösteriyor.
  The instructor demonstrates basic life support.

That contrast is very useful for understanding Turkish passive sentences.