Um ambiente calmo ajuda-me a estudar melhor.

Because ambiente is a masculine noun in Portuguese, so it takes um.

• um ambiente
• o ambiente

This is one of those nouns that may not match what an English speaker expects, since grammatical gender in Portuguese does not always follow natural logic.

Because adjectives usually agree in gender and number with the noun they describe.

Here, calmo describes ambiente, which is masculine singular, so the adjective must also be masculine singular:

• um ambiente calmo
• dois ambientes calmos

If the noun were feminine, you would use calma:

• uma sala calma

In this sentence, ambiente means something like environment, atmosphere, or setting.

It does not only refer to the physical room. It can also refer to the general feeling or conditions around you. So um ambiente calmo could mean:

• a quiet room
• a peaceful atmosphere
• a calm study environment

This is a very important feature of European Portuguese.

In European Portuguese, object pronouns are often attached after the verb with a hyphen. This is called enclisis:

• ajuda-me = helps me
• diz-me = tells me
• explica-me = explains to me

So ajuda-me is the normal European Portuguese form in a simple affirmative sentence.

By contrast, me ajuda is much more typical of Brazilian Portuguese.

The hyphen shows that the pronoun me is attached to the verb.

In European Portuguese spelling, this is standard when the pronoun comes after the verb:

• ajuda-me
• dá-me
• leva-o

So the hyphen is not optional here; it is part of the correct written form.

Me means me and is the object of the verb ajudar.

So:

• ajuda-me = helps me

The subject is um ambiente calmo, and the person receiving the help is me.

Because ajudar commonly follows the pattern:

ajudar alguém a + infinitive

So:

• ajuda-me a estudar
• literally: helps me to study

This is a very common structure in Portuguese. Other examples:

• Ajudas-me a cozinhar. = You help me cook.
• Ela ajuda-o a aprender. = She helps him learn.

Normally, no. With ajudar, Portuguese usually uses a + infinitive in this kind of structure.

So the standard form is:

• ajuda-me a estudar melhor

Without a, it would sound wrong or at least non-standard to most learners of European Portuguese.

Here, melhor works as an adverb, meaning better.

It modifies estudar, not ambiente.

So:

• estudar melhor = to study better

Notice that melhor does not change form here. It stays the same.

Compare:

• um melhor ambiente = a better environment → here melhor is adjectival
• estudar melhor = to study better → here melhor is adverbial

It can suggest both, depending on context.

In um ambiente calmo, the idea is usually that the environment is:

• peaceful
• not stressful
• not noisy
• good for concentration

So in natural English, it might be understood as a calm environment, a peaceful environment, or even a quiet environment, depending on the situation.

Yes, absolutely. Tranquilo is a very natural alternative.

There is a small nuance:

• calmo often emphasizes calmness or lack of agitation
• tranquilo often emphasizes peacefulness, ease, or relaxation

In many everyday contexts, both work well.

Because Um ambiente calmo ajuda-me a estudar melhor follows the most neutral and standard word order in Portuguese:

subject + verb + object/complements

So:

• Um ambiente calmo = subject
• ajuda-me = verb + object pronoun
• a estudar melhor = infinitive phrase

This is the most straightforward way to say it.

Yes, but the original order is the most neutral.

For example, you could hear or read things like:

• Ajuda-me a estudar melhor um ambiente calmo — this sounds unnatural in this context
• A estudar melhor, ajuda-me um ambiente calmo — possible only in a very marked or poetic style

So for normal everyday Portuguese, keep:

• Um ambiente calmo ajuda-me a estudar melhor

Yes, but the meaning changes slightly.

• Um ambiente calmo ajuda-me a estudar melhor = a calm environment helps me study better
• Um ambiente calmo ajuda a estudar melhor = a calm environment helps people study better / helps with studying better in general

So me makes it personal.

Yes, especially because of ajuda-me.

That attached-pronoun structure is a strong sign of European Portuguese. In Brazilian Portuguese, the more usual everyday form would be:

• Um ambiente calmo me ajuda a estudar melhor

Both are understandable, but the version you have is clearly aligned with Portugal.