Вечером мы заказали пасту с креветками, потому что никому не хотелось мяса.

Вечером is the noun вечер in the instrumental case, used adverbially to mean in the evening / during the evening.

This is a very common Russian pattern for times of day:

• утром = in the morning
• днём = in the daytime / during the day
• вечером = in the evening
• ночью = at night

So Вечером мы заказали... means In the evening, we ordered...

You can also say в вечер, but that usually does not mean the same thing in normal speech. For ordinary time expressions, Russian typically uses утром / днём / вечером / ночью.

Заказали is the perfective past tense of заказать, meaning ordered as a completed action.

Here the sentence describes a single finished event:

• We ordered pasta...

That is why perfective makes sense.

Compare:

• Мы заказали пасту. = We ordered pasta.
  (a completed act)
• Мы заказывали пасту. = We were ordering / used to order / did order pasta.
  (more about the process, repetition, or background context)

So заказали is the natural choice when telling what happened that evening.

Because паста is the direct object of заказали, it goes into the accusative case.

Паста is a feminine noun ending in -а, so:

• nominative: паста
• accusative: пасту

So:

• паста = pasta
• заказали пасту = ordered pasta

This is a standard feminine noun pattern:

• книга → книгу
• пицца → пиццу
• паста → пасту

The preposition с meaning with normally requires the instrumental case.

The noun here is креветки (shrimp/prawns), and in the instrumental plural it becomes креветками.

So:

• с креветками = with shrimp

A few similar examples:

• чай с лимоном = tea with lemon
• с сыром = with cheese
• с овощами = with vegetables

Since pasta is commonly described by what it comes with, паста с креветками is a very natural phrase.

Потому что means because.

It introduces a subordinate clause:

• Вечером мы заказали пасту с креветками
• потому что никому не хотелось мяса

In Russian, a subordinate clause introduced by потому что is normally separated by a comma, so the comma here is required.

So the structure is:

• main clause + , потому что
  • reason clause

Example:

• Я остался дома, потому что шёл дождь. = I stayed home because it was raining.

This is because the verb хотеться uses a dative experiencer.

Russian does not say this idea the same way English does. Instead of:

• No one wanted meat

Russian literally builds it more like:

• To no one, meat was wanted

So the person who feels the desire goes in the dative case:

• мне хочется = I feel like / I want
• тебе хочется = you feel like / you want
• ему хочется = he feels like / he wants
• никому не хотелось = nobody felt like / nobody wanted

So никому is the dative form of никто in this kind of structure.

Because хотеться is being used as an impersonal verb here.

In impersonal constructions, Russian often uses:

• 3rd person singular
• in the past, usually neuter singular

So:

• хочется = one feels like / feels a desire
• хотелось = felt like / wanted

That is why the sentence says:

• никому не хотелось мяса

not

• никому не хотели мяса (which would be ungrammatical)

Even though никому refers to people, the verb stays in the impersonal form.

After хотеться, the thing desired is often put in the genitive case, especially with food, substances, or indefinite things.

So:

• nominative: мясо
• genitive: мяса

Thus:

• хотелось мяса = felt like meat / wanted some meat

This is a very common pattern:

• хочется чая = I feel like tea
• хочется кофе = I feel like coffee
• хотелось супа = felt like soup

Using the genitive often gives the sense of some meat/tea/soup, not necessarily a specific item.

It is both normal Russian and somewhat different from English structure.

A very literal breakdown would be:

• никому = to nobody
• не хотелось = it wasn’t desired / there was no desire
• мяса = of meat / for meat

But in natural English, you would usually translate it as:

• nobody felt like meat
• no one wanted meat

So the Russian structure is idiomatic and common, even though the grammar does not match English word-for-word.

Yes. Russian word order is flexible, although different orders can shift emphasis.

The sentence as given is neutral and natural:

• Вечером мы заказали пасту с креветками, потому что никому не хотелось мяса.

Possible variations include:

• Мы вечером заказали пасту с креветками...
• Пасту с креветками мы заказали вечером...

These are still understandable, but they may sound slightly more marked depending on context.

The original version is good because it starts with the time setting (Вечером) and then gives the main action.

The main stresses are:

• вЕчером
• мы заказАли
• пАсту
• с кревЕтками
• потомУ что
• никомУ
• не хотЕлось
• мЯса

Stress is important in Russian because it is not always predictable. For example:

• мЯсо = meat
• мЯса = of meat

If you are learning the sentence aloud, it helps to practice it in chunks:

• ВЕчером мы заказАли
• пАсту с кревЕтками,
• потомУ что никомУ
• не хотЕлось мЯса.