Je ne veux pas en parler maintenant.

Because ne ... pas is the standard way to make a verb negative in French.

• Je veux = I want
• Je ne veux pas = I do not want

In this sentence, the verb being conjugated is veux (from vouloir), so the negation goes around that verb:

• Je ne veux pas...

The infinitive parler stays unchanged.

Because it comes after vouloir.

In French, after a conjugated verb like vouloir (to want), the next verb is usually in the infinitive:

• Je veux manger = I want to eat
• Je veux partir = I want to leave
• Je veux parler = I want to speak / talk

So in Je ne veux pas en parler maintenant, veux is the conjugated verb, and parler stays in the infinitive.

Here, en means something like about it, about that, or of it, depending on context.

It replaces de + noun/thing.
That is because parler often uses de when you say what you are talking about:

• parler de ce problème = to talk about this problem
• en parler = to talk about it

So:

• Je ne veux pas parler de ce problème maintenant can become
• Je ne veux pas en parler maintenant

Because en already includes the idea of de.

Compare:

• parler de quelque chose = to talk about something
• en parler = to talk about it

So you do not say:

• Je ne veux pas en parler de ça ❌

because that would repeat the same idea twice.

Because French object pronouns usually go before the infinitive they belong to.

Here, en belongs with parler:

• parler de cela → en parler

When that infinitive follows another verb like vouloir, the pronoun still stays before the infinitive:

• Je veux en parler
• Je ne veux pas en parler

This often feels unusual to English speakers, because English puts about it after the verb, while French puts en before it.

Yes, in spoken informal French, that is very common.

Native speakers often drop ne in everyday speech:

• Je ne veux pas en parler = standard written and careful spoken French
• Je veux pas en parler = very common in casual speech

For learners, it is best to know both:

• use ne ... pas in writing and formal situations
• expect to hear ne dropped in conversation

That word order is very natural in French.

French often places adverbs like maintenant at the end of the sentence:

• Je ne veux pas en parler maintenant.

It could sometimes appear elsewhere for emphasis, but the end position is the most neutral and common here.

For example:

• Maintenant, je ne veux pas en parler.
  This puts extra focus on now.

But the original sentence sounds the most natural in ordinary use.

Parler means to talk/speak, while dire means to say/tell.

So:

• Je ne veux pas en parler maintenant = I don’t want to talk about it now
• Je ne veux pas le dire maintenant = I don’t want to say it now

French uses parler de for discussing a topic, so en works naturally with parler.

Veux is pronounced roughly like vuh, but with the French vowel eu, which does not exist exactly in English.

A simple pronunciation guide for the whole sentence is:

• Je ne veux pas en parler maintenant
• roughly: zhuh nuh vuh pah zahn par-lay man-teh-nahn

A few useful notes:

• je sounds like zhuh
• veux has a single vowel sound, not two syllables
• en is nasal
• in natural speech, ne may be very weak or disappear

Usually, en replaces de + thing, not a person.

For example:

• Tu parles de ce livre ? → Oui, j’en parle.
• Are you talking about that book? → Yes, I’m talking about it.

If it is a person, French often prefers a full phrase instead of en, especially when clarity matters:

• Je parle de Marie → possible to say J’en parle, but often speakers may repeat the name if needed for clarity

So for learners, the safest rule is:

• think of en mainly as replacing de + thing/idea/topic

Because le and en do different jobs.

• le replaces a direct object
• en replaces de + noun/thing

Since parler here is parler de quelque chose, the correct pronoun is en, not le.

Compare:

• Je veux le voir = I want to see him/it
• Je veux en parler = I want to talk about it

So le would not work for parler de in this sentence.