Nie chcę popełnić błędu.

Literally, the Polish sentence is closer to I don’t want to commit an error:

• nie – not
• chcę – I want
• popełnić – to commit (used for mistakes, crimes, sins, etc.)
• błędu – of a mistake / of an error

English prefers the idiom make a mistake, but Polish typically uses popełnić błąd (commit a mistake/error).

Błędu is the genitive singular form of błąd (mistake).

In the positive sentence, you say:

• Chcę popełnić błąd. – I want to make a mistake.
  
  • błąd is accusative (direct object).

In the negative:

• Nie chcę popełnić błędu. – I don’t want to make a mistake.
  
  • błędu is genitive.

Polish very often changes a direct object from accusative to genitive under negation, especially with a single, countable object:

• Widzę dom. → Nie widzę domu.
• Mam czas. → Nie mam czasu.

So:
popełnić błąd → nie popełnić błędu.

The ending tells you the person:

• chcę – I want (1st person singular)
• chcesz – you want (2nd person singular)
• chce – he/she/it wants (3rd person singular)

So Nie chcę popełnić błędu must be spoken by “I”, not “he/she/it”.
Compare:

• Nie chcę popełnić błędu. – I don’t want to make a mistake.
• Nie chce popełnić błędu. – He/She doesn’t want to make a mistake.

The only difference in writing is that final ę vs e, but it completely changes the subject.

In Polish, when you use a verb like chcieć (to want), the next verb normally stays in the infinitive, just like in English:

• English: I want to make a mistake.
• Polish: Chcę popełnić błąd.

So:

• chcę – is the only verb that is conjugated for person/number.
• popełnić – stays in the infinitive, because it depends on chcę.

Other examples:

• Muszę iść. – I must go.
• Lubię czytać. – I like to read.

This is about aspect:

• popełnić – perfective (one complete act: to commit once)
• popełniać – imperfective (ongoing/habitual: to be committing / to commit repeatedly)

With chcę you usually choose:

• perfective when you talk about one specific action you want (or don’t want) to do:
  
  • Nie chcę popełnić błędu. – I don’t want to make a (single) mistake (now/in this situation).
• imperfective when you talk about a habit or general tendency:
  
  • Nie chcę popełniać błędów. – I don’t want to (tend to) make mistakes / I don’t want to be someone who makes mistakes.

So the original sentence focuses on not making one mistake in this context.

Poles would understand Nie chcę zrobić błędu, but it sounds less natural than Nie chcę popełnić błędu.

Typical patterns:

• popełnić błąd – to commit a mistake (most standard collocation).
• zrobić błąd – to make a mistake (often heard in speech, but more colloquial/less “textbook”).

So:

• Nie chcę popełnić błędu. – most neutral and idiomatic.
• Nie chcę zrobić błędu. – understandable, but stylistically weaker.

You’ll hear zrobić błąd, but if you want best textbook Polish, learn popełnić błąd.

Yes, but there is a nuance:

• błąd – an error, mistake; can sound a bit more serious, often used in school, work, logic, etc.
• pomyłka – a mistake, mix-up; often sounds more casual or like a slip, confusion.

Possible sentences:

• Nie chcę popełnić błędu. – I don’t want to make a mistake (more neutral/serious).
• Nie chcę popełnić pomyłki. – also correct; often used, feels maybe a bit “softer”.

Both are fine; context decides which feels better.

Yes, Polish word order is quite flexible. However, some orders are more natural:

• Most neutral: Nie chcę popełnić błędu.
• Nie chcę błędu popełnić. – Possible, but has a slightly different rhythm/emphasis; sounds more poetic or emphatic.

Usually you keep popełnić błąd together as a verb–object pair. Moving błędu before popełnić is stylistically marked and not what beginners need to aim for.

Approximate pronunciation:

• chcę – roughly [htseh̃]

  • ch – like a hard h (as in Scottish “loch”).
  • c – like ts in cats.
  • ę – nasal e; here it’s often pronounced close to e with slight nasality.

• popełnić – [PO-pew-nʲich] (stress always on the first syllable in Polish):

  • ł – like English w in we.
  • ń – soft n, like ny in canyon.
  • ć – soft ch, similar to the t in British tune or softer ch in chew, but more palatal.

Full sentence: Nie chcę popełnić błędu – [nye htseh popew-nʲich BWEN-doo] (approx.).

No, in the present tense the form chcę does not change with gender.

• A man: Nie chcę popełnić błędu.
• A woman: Nie chcę popełnić błędu.

Same sentence for both.

Gender affects verb forms mainly in the past tense and some participles, e.g.:

• Nie chciałem popełnić błędu. – said by a man.
• Nie chciałam popełnić błędu. – said by a woman.