Preparamos el vehículo para la inspección técnica de vehículos.

Preparamos is the present indicative form of preparar for nosotros/nosotras: we prepare.

So the sentence literally means We prepare the vehicle for the technical vehicle inspection.

In Spanish, the present tense can also sometimes mean:

• a general/habitual action: We prepare
• something happening now: We are preparing

Which meaning is intended depends on context.

Because the sentence needs a conjugated verb that agrees with the subject.

• preparar = the infinitive, to prepare
• prepara = he/she prepares, you prepare (formal singular)
• preparamos = we prepare

Spanish usually changes the verb ending to show who is doing the action, so you do not normally need to say nosotros.

Yes. The full sentence could be:

Nosotros preparamos el vehículo para la inspección técnica de vehículos.

But Spanish often drops subject pronouns when the verb ending already makes the subject clear.
Since preparamos clearly means we prepare, nosotros is usually unnecessary unless you want emphasis or contrast.

Spanish usually uses an article where English might not, or where English is less strict about it.

• el vehículo = the vehicle

In this sentence, it refers to a specific vehicle being prepared, so the definite article el is natural.

Saying just Preparamos vehículo... would sound incomplete or unnatural in standard Spanish.

Para usually means for, in order to, or intended for.

Here it shows the purpose of preparing the vehicle:

• Preparamos el vehículo para la inspección...
• We prepare the vehicle for the inspection

So para links the action to its goal.

In Spain, la inspección técnica de vehículos is the official roadworthiness inspection for vehicles. It is very commonly known by its acronym:

ITV = Inspección Técnica de Vehículos

So in real life, many Spaniards would simply say:

• Preparamos el vehículo para la ITV.

That is often the most natural everyday version.

They do two different jobs:

• el vehículo = the specific vehicle being prepared
• de vehículos = part of the official name of the inspection, meaning of vehicles or for vehicles

So although it may sound repetitive in English, it is normal because inspección técnica de vehículos is a fixed formal expression.

Yes, but it changes the nuance.

• la inspección técnica de vehículos = the official technical vehicle inspection, often the formal or institutional name
• la inspección del vehículo = the inspection of the vehicle

So if you mean the official Spanish test, inspección técnica de vehículos or simply ITV is better.
If you just mean an inspection of a particular vehicle, la inspección del vehículo can work.

Because the personal a is only used with direct objects that are specific people (and sometimes pets or personified beings).

Here, el vehículo is a thing, not a person, so you say:

• Preparamos el vehículo

not

• Preparamos al vehículo

Yes, often, if you specifically mean a car.

• vehículo = vehicle (more general, more formal)
• coche = car (very common in Spain)

So depending on context, you might hear:

• Preparamos el coche para la ITV.

That sounds very natural in Spain if you are talking about a car.

Because it agrees with inspección, which is a feminine noun.

• la inspección
• técnica

So:

• inspección técnica

If the noun were masculine, the adjective would usually be masculine too.

Vehículo has a written accent because of Spanish stress rules.

It is pronounced roughly as:

ve-HI-cu-lo

Without the accent mark, the stress would follow the normal spelling rules and fall in the wrong place.
The accent shows that the stressed syllable is hí.

A rough pronunciation guide for an English speaker is:

preh-pah-RAH-mos el beh-EE-koo-loh PAH-rah lah inspek-THYON TEK-nee-kah deh beh-EE-koo-los

In much of Spain:

• ci in inspección sounds like thy in Castilian pronunciation
• v and b are pronounced very similarly

In Latin American pronunciation, inspección would sound more like:

inspek-SYON

Yes, but the original order is the most neutral.

Standard:

• Preparamos el vehículo para la inspección técnica de vehículos.

Other possible orders for emphasis:

• Para la inspección técnica de vehículos, preparamos el vehículo.

That version is possible, but it sounds more marked or emphatic. For normal use, the original sentence is best.

In everyday Spain Spanish, many people would usually shorten it to:

• Preparamos el vehículo para la ITV.

That is the most common everyday way to refer to the official inspection. The full version is correct, but it sounds more formal or official.