Разум помогает нам принимать решения.

Нам is the dative case of мы (we).

The verb помогать (to help) normally takes:

• the person being helped in the dative
• the action or thing helped with after that

So:

• помогает нам = helps us
• literally: helps to us

This is very common in Russian:

• Он помогает мне. = He helps me.
• Ты помогаешь ей. = You help her.

So in your sentence, нам is there because помогать requires the dative.

Помогает is the present tense, 3rd person singular, from the imperfective verb помогать.

That matches разум, which is singular:

• разум помогает = reason/mind helps

Compare:

• помогает = helps / is helping
• поможет = will help
• помочь = to help

So:

• Разум помогает нам... = Reason helps us...
• Разум поможет нам... = Reason will help us...
• Разум может помочь нам... = Reason can help us...

Because after помогает нам, Russian often uses an infinitive to say helps us do something.

Structure:

• помогать кому? + infinitive

So:

• помогает нам принимать = helps us make / helps us to make

Other examples:

• Она помогает мне учиться. = She helps me study.
• Это помогает нам работать быстрее. = This helps us work faster.

So принимать stays in the infinitive because it expresses the action being helped.

Принимать решение / принимать решения is a very common Russian expression meaning to make a decision / make decisions.

Literally:

• принимать = to take / adopt / make
• решение = decision

So принимать решения is the normal collocation here, much like English make decisions.

Russian can also use:

• решать = to decide / solve

But the nuance is slightly different:

• принимать решения focuses on the act of making decisions
• решать is broader and can also mean to solve

Examples:

• Нам нужно принять решение. = We need to make a decision.
• Я решил уйти. = I decided to leave.

In your sentence, принимать решения sounds very natural and standard.

Решения here is plural accusative of решение.

The infinitive принимать takes a direct object, so решения is in the accusative:

• принимать что? → решения

Because решение is a neuter inanimate noun, its plural accusative looks the same as the plural nominative:

• nominative plural: решения
• accusative plural: решения

So even though the form looks unchanged, its role in the sentence is as the direct object:

• принимать решения = to make decisions

Not exactly. Разум and ум are related, but they are not always interchangeable.

Разум usually suggests:

• reason
• rational mind
• intellect
• the faculty of thinking logically

Ум is broader and often more everyday:

• mind
• intelligence
• cleverness
• brains

So in this sentence, разум gives a slightly more abstract, philosophical feeling:

• reason helps us make decisions
• our rational mind helps us make decisions

If you used ум, the sentence might feel a bit more general or everyday, depending on context.

Yes. Russian word order is fairly flexible because case endings show the grammatical roles.

The neutral order here is:

• Разум помогает нам принимать решения.

But you could also say:

• Нам помогает разум принимать решения.
• Принимать решения нам помогает разум.

These versions shift emphasis:

• starting with нам can emphasize us
• starting with принимать решения can emphasize the action

Even so, the original version is the most straightforward and natural for a simple statement.

No. Russian does not use a separate word like English to before the infinitive in this structure.

The infinitive is just the basic verb form:

• принимать = to make / to take in dictionary form

So:

• помогает нам принимать решения literally works like
• helps us make decisions

Russian simply puts the infinitive after the verb without an extra particle.

The stress is:

• разу́м
• помога́ет
• нам
• принима́ть
• реше́ния

So the whole sentence is:

Разу́м помога́ет нам принима́ть реше́ния.

Stress matters in Russian, so it is useful to learn words together with their stressed syllables.

It is usually understood as a general truth or habitual statement:

• Reason helps us make decisions
• The mind helps us make decisions

Russian present tense often covers both:

• what is happening now
• what generally happens

In this sentence, the most natural reading is general:

• this is how reason functions
• this is something reason does in general

Usually no, not in this general sense.

• принимать is imperfective
• принять is perfective

Here, принимать решения means making decisions in general / as an ongoing process, so the imperfective is the natural choice.

Принять решение usually means:

• to make a decision as a completed act
• often one specific decision

So:

• Разум помогает нам принимать решения. = Reason helps us make decisions.
• Разум помогает нам принять решение. = Reason helps us make a decision.

That second version is possible, but it means something more specific and completed.

Russian has no articles like English a or the.

So:

• разум can mean reason, the mind, or a mind, depending on context
• решения can mean decisions or sometimes the decisions, depending on context

You figure out the exact meaning from the situation, not from an article.

In this sentence, English would usually translate it as a general idea:

• Reason helps us make decisions.