Kvalita jídla je dobrá.

Because kvalita normally takes the genitive: kvalita čeho? = the quality of what?

• jídlo = food
• jídla = of food / of the food in the genitive singular

So kvalita jídla literally has the structure quality of food.

This is very common in Czech:

• cena jídla = the price of the food
• barva auta = the color of the car
• chuť kávy = the taste of the coffee

No. Here jídla is singular genitive of jídlo.

That can be confusing, because jídla can also be plural nominative/accusative in other contexts.

Here, the structure makes it clear:

• kvalita jídla = quality of the food

Not:

• kvalita jídla = quality foods

So in this sentence, jídla is not plural.

Because dobrá agrees with kvalita, and kvalita is a feminine singular noun.

In Czech, adjectives must match the noun they describe in:

• gender
• number
• case

Here:

• kvalita = feminine singular nominative
• so the adjective must be dobrá

Compare:

• film je dobrý = the film is good
• jídlo je dobré = the food is good
• kvalita je dobrá = the quality is good

Even though jídla is nearby, dobrá does not agree with jídla. It agrees with kvalita, which is the subject.

Je is the 3rd person singular present of být = to be.

So:

• já jsem = I am
• ty jsi = you are
• on/ona/ono je = he/she/it is

In this sentence, je links the subject kvalita jídla with the description dobrá.

Unlike in some other Slavic languages, Czech normally does use the verb to be in the present tense:

• Kvalita jídla je dobrá.

You usually cannot just drop je in a normal sentence.

Because dobrá is not directly attached to the noun inside one noun phrase. It is part of the predicate after je.

So the structure is:

• Kvalita jídla = the subject
• je = is
• dobrá = predicate adjective

This is like English The quality of the food is good.

If you put the adjective directly before the noun, you get a different structure:

• dobrá kvalita jídla = good food quality / a good quality of food

That is a noun phrase, not a full sentence.

So:

• Kvalita jídla je dobrá. = full sentence
• dobrá kvalita jídla = noun phrase

Yes, but it does not mean exactly the same thing.

• Jídlo je dobré. = The food is good.
• Kvalita jídla je dobrá. = The quality of the food is good.

The first talks directly about the food. The second focuses specifically on its quality.

In many situations they may feel similar, but the second is a bit more formal or specific.

No. Czech has no articles like English the and a/an.

So kvalita jídla je dobrá can mean:

• the quality of the food is good
• food quality is good
• the quality of food is good

The exact interpretation depends on context.

English speakers often look for an article, but Czech simply does not require one.

Yes. Kvalita jídla je dobrá. is a normal, neutral word order.

A basic Czech sentence often follows:

• subject + verb + complement

Here:

• Kvalita jídla = subject
• je = verb
• dobrá = complement

Czech word order is more flexible than English, so other orders are possible, but they change the emphasis.

For example:

• Dobrá je kvalita jídla. = marked; emphasizes good
• Je dobrá kvalita jídla. = less neutral in ordinary use

For a learner, the given sentence is the safest and most standard version.

A few important points:

• í in jídla is a long vowel
• á in dobrá is also a long vowel
• j in Czech is pronounced like English y in yes

Roughly:

• jídla ≈ yeed-lah
• dobrá ≈ doh-braa

More carefully:

• jí- has a long ee sound
• do- is a pure o
• brá has a long aa

Also note:

• Czech stress is usually on the first syllable
• so: JÍ-dla, DO-brá

Kvalita is in the nominative singular.

It is the subject of the sentence:

• Kvalita jídla = the quality of the food

You can tell because it is the thing being described as dobrá.

So the case pattern is:

• kvalita = nominative subject
• jídla = genitive dependent noun after kvalita

This is a very useful pattern to recognize:

• X in nominative + Y in genitive
  meaning X of Y

Yes. After být (to be), Czech often uses an adjective in the correct agreeing form.

Examples:

• Film je dobrý. = The film is good.
• Káva je dobrá. = The coffee is good.
• Pivo je dobré. = The beer is good.
• Restaurace je dobrá. = The restaurant is good.

The form changes depending on the noun:

• dobrý = masculine
• dobrá = feminine
• dobré = neuter

So in your sentence, dobrá is exactly what we expect because kvalita is feminine.