Gli autoscontri girano vicino alla giostra.

Here, gli is not the pronoun to him. It is the masculine plural definite article, meaning the.

So in this sentence:

• gli autoscontri = the bumper cars

Italian gli can have more than one job, so this is a very common point of confusion.

Because autoscontri is a masculine plural noun that begins with a vowel.

For masculine plural nouns, Italian uses:

• i before most consonants: i libri
• gli before vowels and certain special consonant sounds: gli amici, gli studenti

Since autoscontri starts with a-, the correct article is gli.

Autoscontri is plural.

The singular is:

• l'autoscontro = the bumper car

The plural is:

• gli autoscontri = the bumper cars

Also, in Italian, gli autoscontri can refer not only to the individual cars, but also to the bumper-car attraction in general.

It can mean either, depending on context.

In everyday Italian, gli autoscontri often refers to the bumper-car attraction as a whole, even though the noun is grammatically plural. So the sentence may describe:

• the actual bumper cars moving around, or
• the bumper-car ride area at the fair

This is very natural in Italian.

Girano is the third-person plural present tense of girare.

It is plural because the subject is plural:

• gli autoscontri → plural
• girano → plural verb form

Compare:

• L'autoscontro gira = The bumper car goes around
• Gli autoscontri girano = The bumper cars go around

So this is basic subject-verb agreement.

In this sentence, girare means something like:

• to go around
• to move around
• to circle
• to spin / turn

With amusement rides, it often gives the idea of moving around in operation.

So gli autoscontri girano does not necessarily mean that the whole structure rotates like one object. It more naturally suggests that the bumper cars are moving around nearby.

Because vicino is normally followed by a when it means near:

• vicino a = near

So you first get:

• vicino a la giostra

But Italian combines a + la into alla:

• a + la = alla

That gives:

• vicino alla giostra

Alla is a contraction of:

• a
  • la = alla

So:

• alla giostra literally means to the ride / at the ride / near the ride, depending on context

In this sentence, it is part of the expression vicino a, so the full meaning is simply:

• near the merry-go-round / near the ride

Because here vicino is being used in the expression vicino a, which works like a prepositional phrase meaning near.

In this use, it usually stays as vicino:

• Gli autoscontri girano vicino alla giostra

But when vicino is used as a normal adjective directly describing a noun, it can agree:

• le case vicine = the nearby houses
• i negozi vicini = the nearby shops

So in your sentence, vicino does not need to match autoscontri.

Giostra often means:

• merry-go-round
• carousel

But in fairground/amusement-park contexts, it can also be used more broadly for a ride.

So depending on context, alla giostra could suggest:

• near the carousel, or
• near another fairground ride

If the meaning has already been given to the learner, the main thing to remember is that giostra is a common amusement-park word.

No, Italian word order is often more flexible than English.

The neutral order here is:

• Gli autoscontri girano vicino alla giostra.

But you could also say:

• Vicino alla giostra girano gli autoscontri.

That version puts more emphasis on where they are.

So the original sentence is perfectly normal, but it is not the only possible order.

Gli is one of the trickier Italian sounds for English speakers.

As an article, it is pronounced roughly like:

• lyee

but that is only an approximation. It is not like English glee.

So:

• gli autoscontri sounds roughly like lyee au-toh-SKON-tree

A learner-friendly full approximation of the sentence is:

• lyee au-toh-SKON-tree JEE-ra-no vee-CHEE-no AL-la JOS-tra

That is only approximate, but it can help at the beginning.

Because Italian normally uses definite articles where English often does too, and sometimes even where English might omit them.

Here the sentence is talking about specific, identifiable things in the scene:

• the bumper cars
• the ride / the carousel

So:

• gli autoscontri = the bumper cars
• alla giostra = at/near the ride

Nothing unusual is happening here; this is standard Italian usage.