Eczanede uzun bir kuyruk var, bu yüzden biraz bekleyeceğim.

Eczanede means in/at the pharmacy. It is eczane + the locative suffix -de.

• eczane = pharmacy
• eczanede = in the pharmacy / at the pharmacy

Turkish often uses case endings where English uses separate words like in, at, or to.

This is due to vowel harmony. The locative suffix has different forms: -de, -da, -te, -ta.

The vowel in the last syllable of eczane is e, so the suffix uses e as well: -de.

So:

• eczane → eczanede

The d/t choice depends on the final consonant of the word, but since eczane ends in a vowel, d is used.

Uzun bir kuyruk literally means a long line/queue.

• uzun = long
• bir = a / one
• kuyruk = tail, queue, line

In this sentence, bir works like the English article a. Turkish does not always need an article, but bir is often used when introducing a singular countable noun in this way.

So:

• uzun kuyruk = long queue
• uzun bir kuyruk = a long queue

Both can occur, but uzun bir kuyruk sounds very natural here.

Turkish commonly uses var to mean there is / there are or exists.

So:

• uzun bir kuyruk var = there is a long queue

This is a very common structure:

• Su var. = There is water.
• Sorun var. = There is a problem.
• Burada bir kafe var. = There is a café here.

So rather than saying something like The queue is long in this sentence, Turkish frames it as There is a long queue.

Turkish word order is flexible, but the most neutral order here is:

place + noun phrase + var

So:

• Eczanede = at the pharmacy
• uzun bir kuyruk = a long queue
• var = there is

This gives: At the pharmacy, there is a long queue.

Turkish often puts the verb or predicate at the end of the clause, so var naturally comes last.

Bu yüzden means therefore, because of this, or for this reason.

It connects the first idea to the result:

• Eczanede uzun bir kuyruk var = There is a long queue at the pharmacy
• bu yüzden = because of that / therefore
• biraz bekleyeceğim = I will wait a bit

Yes, it is very common in both spoken and written Turkish.

Similar expressions include:

• bu nedenle = for this reason, therefore
• onun için = so, therefore, because of that

Biraz means a little, a bit, or for a while, depending on context.

Here it means a bit or for a little while:

• biraz bekleyeceğim = I will wait a bit / I will wait for a while

It softens the statement and makes it sound natural.

Bekleyeceğim comes from the verb beklemek, which means to wait.

It breaks down like this:

• bekle- = wait
• -yecek / -acak = future tense
• -im / -ım / -um / -üm = I

Because of sound and vowel harmony changes, the form becomes:

• bekleyeceğim = I will wait

So the sentence is using the 1st person singular future tense.

The y is a buffer consonant. Turkish often inserts y when one vowel-ending part meets another vowel-beginning part, to make pronunciation smoother.

Here the stem bekle- ends in a vowel sound, and the future ending begins with a vowel, so y appears:

• bekle + ecek → bekleyecek

Then with the I ending:

• bekleyeceğim = I will wait

This is very common in Turkish grammar.

Yes, but the meaning changes slightly.

• bekleyeceğim = I will wait
  This clearly refers to a future action in this situation.

• beklerim = I wait / I would wait / I usually wait
  Depending on context, it can sound more habitual, more general, or sometimes like I guess I’ll wait.

In this sentence, bekleyeceğim is the clearest and most natural choice because it refers to a specific future action caused by the long queue.

The comma separates two connected clauses:

• Eczanede uzun bir kuyruk var
• bu yüzden biraz bekleyeceğim

This is similar to English:

There is a long queue at the pharmacy, so I will wait a bit.

The comma helps show the logical connection, but the important part grammatically is bu yüzden, which links cause and result.

Yes, kuyruk is the normal Turkish word for a queue or line of people waiting.

Its basic meaning is actually tail, but it is also the standard word for a waiting line.

So in a place like a pharmacy, bank, or supermarket:

• kuyruk var = there is a line / there is a queue

This is very natural Turkish.

A fairly literal English-style reordering would be:

There is a long queue at the pharmacy, so I will wait a bit.

The Turkish original keeps the same basic logic, but Turkish usually places the predicate at the end and uses suffixes instead of prepositions. So it is helpful to think of the structure as:

• At the pharmacy
• a long queue
• there is
• because of this
• a bit
• I will wait