Bữa ăn này rất ngon.

In Vietnamese, demonstratives like này (this) usually come after the noun, not before it.

So:

• bữa ăn này = this meal
• literally: meal this

This is a very common pattern in Vietnamese:

• nhà này = this house
• xe này = this car
• người này = this person

So even though English says this meal, Vietnamese says meal this.

Vietnamese often does not use a verb like to be when describing something with an adjective.

So:

• Bữa ăn này rất ngon.
• literally: This meal very delicious.

That is completely natural Vietnamese.

In English, you need is:

• This meal is very delicious.

In Vietnamese, adjectives can function directly as the predicate:

• Cô ấy đẹp. = She is beautiful.
• Trời nóng. = The weather is hot.
• Món này ngon. = This dish is delicious.

So the absence of is is normal.

Bữa ăn means meal.

• bữa = a meal occasion / mealtime
• ăn = to eat

Together, bữa ăn refers to a meal as an eating event or meal in general.

A useful comparison:

• bữa ăn = meal
• món ăn = dish / food item

So:

• Bữa ăn này rất ngon. = This meal is very delicious.
• Món ăn này rất ngon. = This dish is very delicious.

If you are talking about the whole meal experience, bữa ăn fits. If you are talking about one specific food item, món ăn is more likely.

Rất means very.

It comes before the adjective it modifies:

• rất ngon = very delicious / very tasty

Examples:

• rất đẹp = very beautiful
• rất tốt = very good
• rất lạnh = very cold

So the structure here is:

• Bữa ăn này = this meal
• rất ngon = very delicious

You can remove rất and still have a correct sentence:

• Bữa ăn này ngon. = This meal is delicious.

Adding rất just makes it stronger.

Ngon usually means delicious, tasty, or sometimes good to eat.

It is one of the most common adjectives used for food and drinks.

Examples:

• Cơm ngon. = The rice is tasty.
• Phở ngon. = The phở is delicious.
• Cà phê ngon. = The coffee is good/delicious.

For food, ngon is extremely natural. In this sentence, it tells you the meal tastes good.

Yes. The sentence follows a very common Vietnamese pattern:

• [noun phrase] + [degree word] + [adjective]

So here:

• Bữa ăn này = noun phrase
• rất = degree word
• ngon = adjective

This pattern appears everywhere in Vietnamese:

• Ngôi nhà này rất đẹp. = This house is very beautiful.
• Con mèo đó rất dễ thương. = That cat is very cute.
• Bài này rất khó. = This lesson is very difficult.

So the structure is very standard and useful to memorize.

Yes, absolutely. Ngon lắm is very natural.

Both are common:

• Bữa ăn này rất ngon.
• Bữa ăn này ngon lắm.

They are similar, but there is a slight difference in feel:

• rất ngon = very delicious, a bit more neutral/direct
• ngon lắm = very delicious, often sounds a bit more natural or expressive in conversation

You will hear both a lot in spoken Vietnamese.

A rough pronunciation guide for an English speaker is:

• bữa ≈ boo-uh (with a dipping/broken tone)
• ăn ≈ un or uhn with a short vowel
• này ≈ nye / nai with a rising tone
• rất ≈ somewhat like zut or rut, but not exactly; the vowel is short
• ngon ≈ ngwawn or ngon with the ng sound at the beginning

A few pronunciation notes:

• bữa is tricky because of both the vowel combination and the tone.
• ăn has the special Vietnamese letter ă, which is short.
• này has a rising tone.
• ngon begins with ng-, which English speakers often find hard at the start of a word, but Vietnamese uses it normally.

If you are studying pronunciation seriously, it helps to learn both:

• the individual vowel sounds
• the six Vietnamese tones

In this sentence, bữa ăn này most naturally means this meal, referring to one specific meal.

However, in context, it can sometimes feel slightly broader, like:

• this particular meal we are having
• this dining experience
• this meal as a whole

Vietnamese nouns usually do not change form for singular vs. plural the way English nouns do. Context tells you the intended meaning.

Here, though, the most natural interpretation is singular: this meal.

Yes, it is natural and correct.

That said, in casual speech, native speakers might also say things like:

• Bữa ăn này ngon quá. = This meal is so delicious.
• Bữa ăn này ngon lắm. = This meal is very delicious.
• Bữa này ngon thật. = This meal is really delicious.

Your original sentence, Bữa ăn này rất ngon, is perfectly good Vietnamese and easy for learners to understand. It sounds slightly neat and textbook-like, but still natural.