Ben dereotlu yoğurt yapıyorum.

Not usually. In Turkish, the verb ending already shows the subject.

Here, -um in yapıyorum tells you the subject is I. So Ben dereotlu yoğurt yapıyorum and Dereotlu yoğurt yapıyorum can both work.

Using ben often adds emphasis, contrast, or clarity, like:

Ben yapıyorum.
= I’m the one making it.

Because Turkish adjectives and adjective-like modifiers normally come before the noun they describe.

So:

dereotlu yoğurt = dill-flavored / with-dill yogurt

This is the normal Turkish order, just like:

büyük ev = big house
sıcak çay = hot tea

The suffix -lı / -li / -lu / -lü means something like with, having, or containing.

So dereotlu means with dill or dill-containing.

Some similar examples:

peynirli börek = pastry with cheese
sütlü kahve = coffee with milk
zeytinyağlı yemek = food with olive oil

The form changes because of vowel harmony:

• -lı
• -li
• -lu
• -lü

This is because dereotu is a compound noun, and when certain suffixes are added, the final compound marker often drops.

So instead of:

dereotu + lu = dereotulu ✘

you get:

dereotlu ✔

This happens in other common words too. For example:

zeytinyağı → zeytinyağlı

For a learner, the safest approach is to learn dereotlu as the natural correct form.

Because it is being used as an indefinite direct object.

In Turkish, indefinite direct objects usually appear with no accusative ending:

Dereotlu yoğurt yapıyorum.
= I’m making some dill yogurt / dill yogurt in general.

If you were talking about a specific yogurt, you would usually use the accusative:

Dereotlu yoğurdu yapıyorum.
= I’m making the dill yogurt. / I’m making that specific dill yogurt.

So the lack of an ending here suggests the object is non-specific.

It is the present continuous (also called the progressive).

yapıyorum = I am doing / I am making

In Turkish, this form is very common for actions happening:

• right now
• around now
• sometimes in a near-future sense, depending on context

So it often corresponds to English I am making.

It breaks down like this:

yap- = verb stem
-ıyor- = present continuous marker
-um = first person singular ending

So:

yap- + -ıyor + -um = yapıyorum

The vowel in -ıyor is chosen by vowel harmony. Since the last vowel in yap- is a, the suffix appears as -ıyor here.

It absolutely can be.

In fact, Dereotlu yoğurt yapıyorum may sound more natural in many everyday situations, because Turkish often leaves out subject pronouns when they are already clear from the verb.

Adding ben is not wrong. It just gives a bit more emphasis or explicitness.

Yes, but the basic neutral order here is:

(Ben) + dereotlu yoğurt + yapıyorum
Subject + object + verb

Turkish is flexible with word order, but changing the order usually changes the emphasis.

For example:

Dereotlu yoğurt yapıyorum.
Neutral and natural.

Ben dereotlu yoğurt yapıyorum.
Adds emphasis to I.

In ordinary speech, the verb usually stays at the end.

Because Turkish often omits bir when English would use a/an or when the noun is being used in a general or non-specific way.

Also, yoğurt is often treated like a mass noun, similar to water or rice in English.

So:

Dereotlu yoğurt yapıyorum
sounds very natural.

If you said:

Bir dereotlu yoğurt yapıyorum

it would sound more like:

• I’m making a dill yogurt
• one unit/type/portion of dill yogurt

That can be possible in some contexts, but it is less neutral here.

In modern Turkish, ğ usually does not sound like a hard English g.

In yoğurt, the ğ mainly softens the transition and may lengthen the preceding vowel a little. A rough learner-friendly pronunciation is:

yo-urt

So do not pronounce it like: yog-gurt

Also:

• y sounds like English y
• o is like a pure o
• u is like Turkish u, not exactly like English reduced vowels

A close approximation is better than trying to force a hard g sound.