Die Busfahrt ins Zentrum dauert zwanzig Minuten.

Because Fahrt is a feminine noun in German: die Fahrt.

Busfahrt is a compound noun made from Bus + Fahrt, and in German the last part of the compound decides the gender. Since Fahrt is feminine, Busfahrt is also feminine:

• die Fahrt
• die Busfahrt

So die Busfahrt means the bus ride / the trip by bus.

German very often combines nouns into compound nouns. English usually writes these as separate words, but German usually writes them as one word.

So:

• Bus = bus
• Fahrt = ride, journey, trip

Together:

• Busfahrt = bus ride / journey by bus

This is extremely normal in German. You will see this all the time:

• Bahnhof = train station
• Hausaufgabe = homework
• Sommerferien = summer holidays

Ins is a contraction of in das.

• in = in, into, to
• das = the

So:

• ins Zentrum = in das Zentrum

German uses this contraction very often, just like English uses don't for do not.

Because ins Zentrum expresses direction or destination: the bus ride goes into/to the center.

• ins Zentrum = into/to the center
• im Zentrum = in the center

So the difference is:

• Die Busfahrt ins Zentrum... = the bus ride to the center
• Die Busfahrt im Zentrum... = the bus ride in the center

With in, German often uses:

• accusative for movement/direction
• dative for location

Here there is a destination, so accusative is used: in das Zentrum → ins Zentrum.

Because Zentrum is a neuter noun in German.

Its article is:

• das Zentrum = the center

Since in here takes the accusative for direction, and the accusative form of das is still das, you get:

• in das Zentrum
• contracted: ins Zentrum

The verb is dauern, which means to last or to take (time).

So:

• Die Busfahrt dauert zwanzig Minuten.
• literally: The bus ride lasts twenty minutes.

This is a very common way in German to talk about duration.

You can use dauern with many things:

• Der Film dauert zwei Stunden.
• Das Meeting dauert eine Stunde.

German often expresses this idea differently from English.

English commonly says:

• It takes twenty minutes.

German often says:

• Die Busfahrt dauert zwanzig Minuten.
• literally: The bus ride lasts twenty minutes.

So instead of using a dummy subject like it, German simply makes the bus ride the subject.

That is very natural German.

Here zwanzig Minuten is a time expression showing duration. In German, duration is often expressed in the accusative.

So:

• zwanzig Minuten = twenty minutes

You do not see an article here, so the case is not very obvious from the form alone, but this kind of phrase is commonly treated as an accusative expression of duration.

Compare:

• Der Film dauert zwei Stunden.
• Die Reise dauert einen Tag.

Because German main clauses normally follow the verb-second (V2) rule.

In this sentence:

• Die Busfahrt = position 1
• dauert = position 2
• ins Zentrum / zwanzig Minuten = the rest

So:

• Die Busfahrt dauert zwanzig Minuten.

You could move another element to the front, but then the verb still stays second:

• Zwanzig Minuten dauert die Busfahrt ins Zentrum.

That sounds more marked or more literary, but it is grammatical.

Yes. That is also correct.

• die Busfahrt = the bus ride
• die Fahrt mit dem Bus = the ride/trip by bus

The compound Busfahrt is more compact and very natural.
Die Fahrt mit dem Bus is a little more explicit.

Both are fine.

Because all nouns are capitalized in German.

So in this sentence:

• Busfahrt is a noun
• Zentrum is a noun
• Minuten is a noun

That is why they all begin with capital letters.

This is one of the most noticeable spelling rules in German.

Not always.

• ins Zentrum = into/to the center
• zum Zentrum = to the center

In many everyday contexts, both can be translated as to the center, but ins Zentrum often suggests going into the central area, while zum Zentrum can sound more like going toward/to that place.

In this sentence, ins Zentrum is the most natural choice for a trip whose destination is the city center.

A common standard pronunciation is roughly:

• TSVAHN-tsikh

A few useful notes:

• zw sounds like tsv
• the a is short
• the final -ig is often pronounced like -ikh in standard German

So zwanzig Minuten sounds roughly like:

• TSVAHN-tsikh mee-NOO-ten

Regional pronunciations can vary, so you may also hear slightly different versions.