Das Essen schmeckt prima.

Because Essen is being used as a noun, not as the verb essen (to eat).

• essen = to eat
• das Essen = the food / the meal / the eating

German capitalizes all nouns, so Essen must have a capital E here.

In this sentence, das Essen means the food or the meal, not to eat.

Every German noun has a grammatical gender, and Essen is neuter, so it takes das.

• das Essen = the food / the meal

This is something you usually just have to learn together with the noun: not just Essen, but das Essen.

Also, Essen as a noun comes from the verb essen, and many infinitives used as nouns are neuter in German.

It can mean either, depending on context.

In Das Essen schmeckt prima, the most natural English idea is usually:

• The food tastes great.

But in some contexts it could also mean:

• The meal tastes great.

If someone is talking about the quality of what is being served, the food is usually the best fit.

Because the subject is Das Essen, which is third person singular.

The verb schmecken is conjugated like this in the present tense:

• ich schmecke
• du schmeckst
• er/sie/es schmeckt
• wir schmecken
• ihr schmeckt
• sie/Sie schmecken

Since das Essen is singular and treated like es, you need schmeckt.

Schmecken is about taste.

So Das Essen schmeckt prima means the food tastes great, not just that it is great in general.

A useful comparison:

• Das Essen ist prima. = The food is great.
• Das Essen schmeckt prima. = The food tastes great.

The second sentence focuses specifically on flavor.

German often uses schmecken with a dative person:

• Das Essen schmeckt mir prima. = The food tastes great to me / I think the food tastes great.

But the dative can be omitted when the speaker is making a general comment or when the person is obvious from context.

So:

• Das Essen schmeckt prima. = The food tastes great.
• Das Essen schmeckt mir prima. = I think the food tastes great.

Both are correct.

That is a very common question. In German, with schmecken, the thing being tasted is usually the subject.

So German structures the idea like this:

• The food tastes good (to me).

not like this:

• I taste the food well.

If you want to mention the person, German usually puts that person in the dative:

• Das Essen schmeckt mir prima.

Literally, that is something like The food tastes great to me.

Prima means something like:

• great
• excellent
• really good

In this sentence, it describes how the food tastes.

It is a common, natural word in everyday German, though it can sound a bit cheerful or enthusiastic.

Other possibilities are:

• Das Essen schmeckt gut. = The food tastes good.
• Das Essen schmeckt lecker. = The food tastes delicious.
• Das Essen schmeckt hervorragend. = The food tastes excellent.

In this sentence, prima is functioning like an adverbial predicate after schmecken.

The important practical point for learners is: it does not change its form here.

So you say:

• Das Essen schmeckt prima.

not something like:

• Das Essen schmeckt primes or primen

Words like prima, gut, and lecker often stay unchanged in this kind of sentence.

Yes, absolutely.

But there is a small difference:

• Das Essen ist prima. = The food is great.
• Das Essen schmeckt prima. = The food tastes great.

Using schmecken is more specific because it talks about taste. Using sein is more general.

No, this is a very basic German main-clause word order:

• Das Essen = subject
• schmeckt = verb
• prima = complement/adverbial

German main clauses usually put the finite verb in second position, and that is exactly what happens here:

• Das Essen | schmeckt | prima

So this sentence is a good example of standard German word order.

Yes. As a noun, das Essen can mean:

• food
• meal
• eating (depending on context)

For example:

• Das Essen ist fertig. = The meal/food is ready.
• Essen ist wichtig. = Eating is important.

In Das Essen schmeckt prima, the context clearly points to food or the meal, because something that schmeckt is something that has a taste.