На следующей остановке нам нужно выйти из автобуса.

Because Russian normally uses на with остановка when talking about a stop on a route: на остановке = at the stop.

So:

• на следующей остановке = at the next stop
• not в следующей остановке

This is just the standard preposition used with this noun in this meaning.

Also, after на in this kind of location phrase, остановка takes the prepositional case, which is why остановка becomes остановке.

Because следующая is describing остановке, and adjectives in Russian have to match the noun they describe in:

• gender
• number
• case

Here:

• dictionary form: следующая остановка
• in the sentence: на следующей остановке

Since остановке is:

• feminine
• singular
• prepositional case

the adjective must also be feminine singular prepositional:

• следующей

So the phrase changes together:

• следующая остановка
• на следующей остановке

Because Russian often uses a structure like:

• кому-то нужно + infinitive

This literally works more like:

• to someone, it is necessary to...

So:

• нам нужно выйти = we need to get off / it is necessary for us to get off

That is why нам is in the dative case:

• я → мне
• ты → тебе
• мы → нам
• они → им

You should think of нужно here as part of an impersonal construction, not as a verb that takes a normal subject like English we need.

Нужно means necessary / need to in an impersonal construction.

In sentences like this, Russian often does not use a personal verb equivalent to English need. Instead, it uses words like:

• нужно = need to / it is necessary
• надо = need to / have to
• необходимо = necessary

Examples:

• Мне нужно идти. = I need to go.
• Нам нужно выйти. = We need to get off.
• Тебе надо учиться. = You need to study.

So in your sentence, нужно is not changing for person or number the way an English verb would.

Because выйти is the perfective form, and here Russian is talking about a single completed action:

• getting off the bus at one specific stop

Compare:

• выходить = imperfective, process / repeated / general action
• выйти = perfective, one completed action

In this sentence, the idea is:

• At the next stop, we need to get off
  → one action, completed at that stop

So выйти is the natural choice.

If you used выходить, it would sound more like a general or repeated action in the right context, not this one specific moment.

Because Russian uses из to mean out of / from inside, and a bus is treated as something you are inside.

So:

• выйти из автобуса = to get out of the bus / get off the bus
• из requires the genitive case

That is why:

• автобус → автобуса

This pattern is very common:

• выйти из машины = get out of the car
• выйти из дома = leave the house
• выйти из метро = come out of the metro

Standard Russian uses из автобуса.

• выйти из автобуса = standard, neutral, correct

You may sometimes hear с автобуса in regional or colloquial speech, but for a learner, из автобуса is the form to use.

A useful rule:

• if you are coming out from inside something, use из
• if you are coming down/off from a surface, use с

So a bus is normally treated as something you are inside, not on top of.

Yes, Russian word order is flexible.

This version puts emphasis first on when/where the action happens:

• На следующей остановке = At the next stop

Then comes the need:

• нам нужно

Then the action:

• выйти из автобуса

Other word orders are possible, for example:

• Нам нужно выйти из автобуса на следующей остановке.
• Из автобуса нам нужно выйти на следующей остановке.

These all mean basically the same thing, but the focus shifts slightly.

The original sentence sounds very natural if the speaker wants to highlight the next stop.

Here is the breakdown:

• на следующей остановке
  • остановке = prepositional case
  • used after на for location/time in this expression
• нам
  • dative case
  • used with нужно
• из автобуса
  • автобуса = genitive case
  • used after из

So the sentence is a good example of how Russian uses cases to show relationships that English often shows with word order or prepositions alone.

Yes, sometimes it can, if the context already makes it clear who needs to get off.

For example:

• На следующей остановке нужно выйти из автобуса.

This can mean something like:

• At the next stop, we need to get off
• At the next stop, you need to get off
• At the next stop, one has to get off

So нам is useful because it clearly tells you that the speaker means we.

Yes, in this sentence they are very close in meaning.

• Нам нужно выйти из автобуса.
• Нам надо выйти из автобуса.

Both mean we need to get off the bus.

A rough difference:

• надо often sounds a bit more conversational
• нужно can sound slightly more neutral or matter-of-fact

But in everyday speech, both are extremely common, and in this sentence either one works well.

A simple pronunciation guide is:

Na SLYE-doo-yush-chey a-sta-NOF-kye nam NOOZH-na VY-ti iz af-TO-boo-sa.

A few helpful notes:

• следующей is often hard for learners because of the consonant cluster
• остановке has stress on -нов-
• нужно is pronounced roughly NOOZH-na
• выйти has stress on the first syllable: VY-ti
• автобуса has stress on то: af-TO-boo-sa

You do not need perfect transliteration, but getting the stress right helps a lot.