Когда мне трудно сосредоточиться, я делаю паузу и выхожу на балкон.

Because the sentence begins with a subordinate clause introduced by когда (when):

Когда мне трудно сосредоточиться, я делаю паузу и выхожу на балкон.

In Russian, when a clause like when..., if..., because... comes before the main clause, it is separated by a comma.

• Когда мне трудно сосредоточиться = when it is hard for me to concentrate
• я делаю паузу и выхожу на балкон = I take a pause and go out onto the balcony

If the order were reversed, you would still use a comma:

Я делаю паузу и выхожу на балкон, когда мне трудно сосредоточиться.

This is a very common Russian pattern. Russian often expresses feelings or states with:

• dative pronoun/noun + adverb/state word + infinitive

So:

• мне трудно = literally to me, it is difficult
• мне трудно сосредоточиться = it is hard for me to concentrate

The pronoun мне is in the dative case, not nominative, because Russian is not saying I am difficult or I am struggling in the same grammatical way English does. It is describing a state affecting you.

Compare:

• Мне трудно работать. = It’s hard for me to work.
• Ему легко учиться. = It’s easy for him to study.
• Нам сложно понять. = It’s difficult for us to understand.

Трудно here means difficult / hard and functions as a predicative adverb or state word.

In this kind of sentence, Russian often uses words like:

• трудно = hard
• легко = easy
• сложно = difficult/complicated
• интересно = interesting
• приятно = pleasant

So мне трудно сосредоточиться is literally something like:

• to me [it is] hard to concentrate

There is no separate word for it is in the present tense, because Russian usually omits the present-tense form of to be.

Because after words like трудно, легко, можно, нельзя, Russian often uses an infinitive to say what action is hard, easy, possible, or impossible.

So:

• мне трудно сосредоточиться = it is hard for me to concentrate
• мне трудно вставать рано = it is hard for me to get up early
• ему легко читать по-русски = it is easy for him to read in Russian

This is very natural in Russian and is one of the standard ways to express it is hard/easy to do something.

This is about verbal aspect.

• сосредоточиться = perfective
• сосредотачиваться = imperfective

In this sentence, the idea is to manage to get focused / to achieve concentration, not the ongoing process in general. That is why the perfective verb сосредоточиться sounds natural here.

So мне трудно сосредоточиться means something like:

• it’s hard for me to get focused
• it’s hard for me to concentrate

If you used the imperfective сосредотачиваться, it would emphasize the process or repeated activity more, and in this exact sentence it would sound less standard.

This is a common pattern:

• Мне трудно проснуться. = It’s hard for me to wake up.
• Ей трудно решиться. = It’s hard for her to make up her mind.

The perfective often appears when the difficulty is in reaching a result.

Yes—literally, that is exactly how it works.

• делать паузу = to take/make a pause

English usually says take a break or pause, but Russian commonly uses the noun пауза with the verb делать:

• Я делаю паузу. = I pause / I take a break.
• Давай сделаем паузу. = Let’s take a break.

This is just a normal Russian collocation. It may sound slightly more formal or neutral than делаю перерыв, but both are understandable in many contexts.

Because the sentence describes a habitual or repeated action: when this happens, I do this.

• делаю is imperfective, present tense
• it means something like I take a pause as a regular response

The whole sentence has a general, habitual meaning:

• When it’s hard for me to concentrate, I take a pause and go out onto the balcony.

If you used сделаю, it would normally point to a single completed future action, not a general routine.

Compare:

• Когда мне трудно сосредоточиться, я делаю паузу.
  = Whenever it’s hard for me to concentrate, I take a pause.

• Когда мне станет трудно сосредоточиться, я сделаю паузу.
  = When it becomes hard for me to concentrate, I will take a pause.

Because выходить / выйти means to go out / to step out, and that fits a balcony very naturally.

• выхожу на балкон = I go out onto the balcony

A balcony is often thought of as a space you step out onto from inside a room, so Russian commonly uses выходить на балкон.

You could sometimes say иду на балкон, but it is less specific. It just means I’m going to the balcony, while выхожу на балкон highlights the movement outward from inside.

So in this sentence, выхожу is the most natural choice.

This is about motion vs. location.

With places like балкон, Russian uses:

• на балкон = onto the balcony, motion toward it
• на балконе = on the balcony, location

So:

• Я выхожу на балкон. = I go out onto the balcony.
• Я стою на балконе. = I am standing on the balcony.

You would not say в балкон, because a balcony is treated as a surface/platform-type place, not an enclosed space you go into.

This is similar to:

• на улицу / на улице
• на сцену / на сцене

Because in Russian, the present tense is often used for habitual actions, just like in English.

So:

• Когда мне трудно сосредоточиться, я делаю паузу и выхожу на балкон.

means:

• When it’s hard for me to concentrate, I take a pause and go out onto the balcony.
• or more naturally in English, Whenever I have trouble concentrating, I take a break and go out onto the balcony.

Russian does not need a special tense for this kind of repeated routine. The present tense is enough.

Because both verbs have the same subject: я.

Russian, like English, does not need to repeat the subject if it clearly applies to both verbs:

• я делаю паузу и выхожу на балкон
  = I take a pause and go out onto the balcony

Repeating я would be grammatically possible, but unnecessary here:

• я делаю паузу и я выхожу на балкон

That version sounds heavier and more emphatic. Normally, Russian uses just one я.

Yes. Russian word order is flexible, although the original version is very natural and neutral.

Original:

• Когда мне трудно сосредоточиться, я делаю паузу и выхожу на балкон.

You could also say:

• Я делаю паузу и выхожу на балкон, когда мне трудно сосредоточиться.

The meaning stays basically the same, but the focus shifts slightly:

• starting with Когда... sets the situation first
• starting with Я делаю... emphasizes what you do first

For a learner, the original sentence is a good standard model.