Если промокод не даст скидку, я оформлю возврат и закажу другой товар.

Yes. Если means if and introduces a condition:

Если промокод не даст скидку = If the promo code doesn’t give a discount

One important difference from English is that Russian can use a future form after если when the meaning is about a future result. English usually says if the promo code doesn’t work / doesn’t give a discount, not if it won’t give a discount.

So in Russian, this is completely normal:

• Если X случится, я Y = If X happens, I will Y

Даст is the future tense of дать (to give).
Here the speaker is talking about a possible future situation: what will happen if the promo code fails to produce a discount.

• даёт / дает = gives / is giving (present)
• даст = will give

So:

• Если промокод не даёт скидку... would sound more like a general or current statement: If the promo code isn’t giving a discount / doesn’t give a discount
• Если промокод не даст скидку... means If the promo code doesn’t give a discount (when I try it / in this case in the future)

Because the speaker is describing what they will do in response to that condition.

• я оформлю возврат = I will arrange/process a return
• и закажу другой товар = and I will order another item

Russian often uses the future in both parts of this kind of sentence:

• Если будет проблема, я позвоню.
• If there is a problem, I’ll call.

That is different from English, where we usually say:

• If there is a problem, I’ll call not
• If there will be a problem, I’ll call

It breaks down like this:

• Если = if
• промокод = promo code
• не даст = does not give / will not give
• скидку = a discount
• я оформлю = I will arrange / process
• возврат = a return
• и = and
• закажу = I will order
• другой товар = another item / a different product

So the pattern is:

If + condition, I will do X and Y.

Because it is the direct object of дать (to give), so it is in the accusative case.

Dictionary form:

• скидка = discount

Accusative singular:

• скидку

Compare:

• Промокод даст скидку. = The promo code will give a discount.

This is a very common pattern:

• дать совет = give advice
• дать ответ = give an answer
• дать скидку = give a discount

Because возврат is also the direct object of the verb оформить.

• оформить возврат = to arrange/process a return

Since возврат is masculine and inanimate, its accusative singular looks the same as the nominative singular:

• nominative: возврат
• accusative: возврат

So the form does change by case grammatically, but here it just happens to look identical.

It means something like:

• to process a return
• to arrange a return
• to make a return request

This is a very common customer-service / shopping phrase in Russian.

A few related expressions:

• сделать возврат = make a return
• оформить возврат = process/arrange a return
• вернуть товар = return an item

In this sentence, оформлю возврат sounds natural and fairly standard for online shopping or customer support.

It can mean both, depending on context.

• другой товар = another item / a different product

Here it probably means: the speaker will return this item and order a different one instead.

Grammar:

• другой agrees with товар
• товар is masculine singular
• so the adjective is also masculine singular: другой

Examples:

• Я закажу другой товар. = I’ll order another/different product.
• Мне нужен другой размер. = I need another/a different size.

Because the sentence begins with a subordinate clause introduced by если:

• Если промокод не даст скидку, ...

In Russian, subordinate clauses are normally separated by commas. So this punctuation is standard.

Compare:

• Если будет дождь, мы останемся дома.
• If it rains, we’ll stay home.

The comma is required in Russian here.

Yes, Russian word order is fairly flexible, though the original version is the most neutral and natural.

Original:

• Если промокод не даст скидку, я оформлю возврат и закажу другой товар.

Possible variations:

• Я оформлю возврат и закажу другой товар, если промокод не даст скидку.
• Если промокод скидку не даст, я оформлю возврат и закажу другой товар.

These all mean basically the same thing, but word order can slightly change emphasis.

The original is a very normal, straightforward way to say it.

Yes, it can often be omitted because the verb ending already shows the subject:

• оформлю = I will arrange
• закажу = I will order

So this is also possible:

• Если промокод не даст скидку, оформлю возврат и закажу другой товар.

But including я is perfectly natural too. It can make the sentence slightly clearer or more explicit, especially in conversation or when contrasting who will do what.

All the main verbs here are perfective:

• дать → даст
• оформить → оформлю
• заказать → закажу

Perfective verbs focus on a completed result or single whole action.

That fits the meaning here:

• the promo code either does or does not produce a discount
• the speaker will complete the return process
• the speaker will place a new order

If you used imperfective verbs, the meaning would shift and often sound less appropriate here.

For example:

• заказывать is more about the process or repeated action
• заказать is about placing the order as a completed action

So perfective aspect is the natural choice in this sentence.

Yes. Промокод is a very common modern Russian word meaning promo code.

It is borrowed from English-based commercial vocabulary, and you will often see it in online shopping, apps, and ads.

Examples:

• Введите промокод = Enter the promo code
• Промокод не работает = The promo code doesn’t work
• По промокоду будет скидка = There will be a discount with the promo code

So this sentence sounds natural in an e-commerce context.