Learn Hardcore French: Cette émission porte sur la musique française.

Literal porter means to carry, but in this expression you should just remember porter sur + noun as:
Le film porte sur la guerre. → The film is about the war.
Le débat porte sur l’éducation. → The debate is about education.

So in Cette émission porte sur la musique française, porte sur = is about / focuses on.
Don’t try to translate porte literally as carries here.

Why is it cette émission and not ce émission or cet émission?

Because émission is a feminine noun, so the demonstrative adjective has to be feminine singular:

Masculine singular: ce (before a consonant) → ce film
Masculine singular: cet (before a vowel or mute h) → cet homme
Feminine singular: cette → cette émission
Plural (both genders): ces → ces émissions

Émission is grammatically feminine (une émission, l’émission), so you must use cette émission.

What exactly does émission mean? Is it the same as show or program?

Émission generally means a broadcast, that is, a radio or TV show/program.

Typical uses:

une émission de radio → a radio show
une émission de télévision → a TV program

Some related words:

un spectacle – a live show, performance (concert, play, etc.), not a broadcast.
un programme – can mean schedule (TV listings) or sometimes show, but émission is the standard word for a specific TV/radio show.

So Cette émission is best understood as This (radio/TV) show / This program.

Why is it la musique française and not la française musique?

In French, most adjectives come after the noun, especially:

Adjectives of nationality (français, italien, américain…)
Adjectives of color, shape, origin, etc.

So:

la musique française = the French music
les films italiens = Italian films
la cuisine japonaise = Japanese cuisine

Putting the adjective before the noun (la française musique) is incorrect in this case. Nationality adjectives like français / française normally follow the noun they modify.

Why is it française and not français?

Because adjectives in French must agree in gender and number with the noun they describe.

The adjective français has these main forms:

Masculine singular: français
Feminine singular: française
Masculine plural: français
Feminine plural: françaises

Here, the noun is la musique:

musique is feminine singular
therefore the adjective must also be feminine singular: française

So:

la musique française – French music
un film français – a French film (masc. sing.)
des chansons françaises – French songs (fem. pl.)

Does la musique française mean French music in general, or some specific French music?

With the definite article la, la musique française usually means French music as a whole, the general category:

Cette émission porte sur la musique française.
→ The show is about French music in general.

French often uses le / la / les to talk about things in a general sense:

J’aime la musique classique. → I like classical music (as a genre).
La littérature française est très riche. → French literature is very rich.

It could refer to specific music if the context makes that clear, but on its own it naturally suggests the general subject of French music.

Can I omit the article and say Cette émission porte sur musique française?

No. In standard French you cannot say porte sur musique française without a determiner.

French almost always requires some kind of determiner (article, possessive, demonstrative, etc.) before a noun used as a subject or object:

sur la musique française (definite article)
sur de la musique française (partitive – some French music)
sur cette musique française (this French music)
sur une musique française (a French piece of music, in some contexts)

But sur musique française is incorrect. You need la (or another determiner).

Why is the preposition sur used here instead of de?

Because the expression is porter sur + noun. The preposition sur belongs to this specific verb pattern.

Sur in this type of structure often means about / on the subject of:

un livre sur la musique → a book about music
un documentaire sur la guerre → a documentary about the war
Le débat porte sur l’immigration. → The debate is about immigration.

Other verbs take other prepositions:

parler de → parler de la musique française (to talk about French music)
discuter de → discuter de ce problème (to discuss this problem)

So with porter, you say porter sur quelque chose, not porter de quelque chose.

Could I say Cette émission parle de la musique française or Cette émission est sur la musique française instead? Are they correct?

Yes, but there are nuances:

Cette émission parle de la musique française.
- Fully correct and very common.
- Emphasizes that the show talks about French music.
Cette émission porte sur la musique française.
- Also fully correct and a bit more neutral/formal.
- Emphasizes that the topic/focus of the show is French music.
Cette émission est sur la musique française.
- Widely used in everyday speech, influenced by English is about.
- Many speakers say it, but in formal writing teachers and style guides usually prefer porte sur or parle de.

So parle de and porte sur are both good choices; est sur is common but slightly more colloquial / less traditional.

What is the infinitive of porte, and how is it conjugated here?

The infinitive is porter, a regular -er verb.

In the sentence Cette émission porte sur la musique française, porte is:

present tense
3rd person singular (il/elle/on porte)
subject: cette émission (feminine singular, but 3rd person singular like il/elle)

Present tense of porter:

je porte
tu portes
il / elle / on porte
nous portons
vous portez
ils / elles portent

So grammatically, porte here is “it is about / it focuses on”.

What happens to the meaning if I change the position of française, for example Cette émission française porte sur la musique?

The meaning changes because the adjective attaches to a different noun:

Cette émission porte sur la musique française.
→ The topic is French music. The show could be French or foreign; the sentence doesn’t say.
Cette émission française porte sur la musique.
→ The show itself is French, and its topic is music (in general).

So:

française after musique → describes musique
française after émission → describes émission

French adjective placement is important: the adjective normally follows the noun it modifies (with some exceptions), so position clearly signals what it is describing.

Are there other ways to say about here, like au sujet de or à propos de?

Yes, but they sound a bit different:

Cette émission est au sujet de la musique française.
Cette émission est à propos de la musique française.

These are grammatically correct, but in this particular sentence they sound more formal or slightly awkward compared with the natural porte sur or parle de.

Au sujet de and à propos de are often used:

in more formal language: un rapport au sujet de la pollution
or as short comments: À propos de ça, j’ai une question.

For a TV/radio show description, porte sur or parle de is more idiomatic.

How should I pronounce the sentence Cette émission porte sur la musique française?

Key points:

Cette émission → [sɛt‿emisjɔ̃]
- cette: [sɛt]; the t is pronounced.
- There is a liaison: t links to the é in émission, sounding like set-tay.
émission → [emisjɔ̃]
- é: like ay in say.
- ss: [s].
- -tion: [sjɔ̃], with a nasal ɔ̃ at the end.
porte → [pɔʁt]
- Final e is silent; t is pronounced.
sur → [syʁ]
- u: rounded u sound (like the French u in tu), not like English oo.
la musique → [la myzik]
- musique: que is [k]; final e silent.
française → [fʁɑ̃sɛz]
- Final -se is pronounced as [z]; you hear a final consonant.
- The an is nasal [ɑ̃].

Spoken naturally, it flows roughly as:
[sɛt‿emisjɔ̃ pɔʁt syʁ la myzik fʁɑ̃sɛz].