¿Podría usted decirme si sin brújula es fácil perderse cerca de la cueva?

Podría is the conditional form of poder and makes the question more polite and less direct.

• ¿Puede usted decirme...? = Can you tell me...?
• ¿Podría usted decirme...? = Could you tell me...?

In English, could often sounds more polite than can, and the same idea applies here.

Usted is the formal you. It adds politeness and formality.

It is not strictly necessary, because Spanish often leaves subject pronouns out:

• ¿Podría decirme si...?
• ¿Podría usted decirme si...?

Both are correct. Including usted can sound a bit more formal or emphatic.

For Spain specifically, usted is used, but in many everyday situations people often prefer tú unless the situation is clearly formal.

Because when a pronoun goes with an infinitive, it is usually attached to the end:

• decirme = to tell me
• ayudarme = to help me
• explicarme = to explain to me

So:

• ¿Podría usted decirme...? is correct.

You can also move the pronoun before the conjugated verb:

• ¿Me podría usted decir...?

Both are correct. This sentence uses the attached version.

Here si introduces an indirect yes/no question, so it means if or whether.

• ¿Podría usted decirme si... ? = Could you tell me if / whether... ?

This is different from a conditional if sentence like Si llueve, no salgo.

In your sentence, si does not mean a condition. It introduces the thing you want to know.

After sin, Spanish often leaves out the article when speaking generally.

• sin brújula = without a compass
• sin dinero = without money
• sin coche = without a car

Sin una brújula is possible, but it can sound more specific or less natural in many contexts. Here, sin brújula is the normal general way to say it.

Because perderse means to get lost, while perder by itself usually means to lose something.

• perder = to lose
  
  • Perdí las llaves = I lost the keys
• perderse = to get lost
  
  • Me perdí en el bosque = I got lost in the forest

So in this sentence, es fácil perderse means it is easy to get lost.

In Spanish, after es fácil, the normal structure is:

• es fácil + infinitive

So:

• Es fácil perderse
• Es difícil encontrar la cueva
• Es peligroso caminar de noche

You do not normally use de before the infinitive in this kind of structure.

Yes, Spanish word order is flexible, and other versions are possible.

This sentence is understandable, but many learners may find this version more natural:

• ¿Podría usted decirme si es fácil perderse cerca de la cueva sin brújula?

That order puts the main idea first:

• si es fácil perderse...

and leaves sin brújula until the end as the condition.

Both are grammatical, but the alternative may sound smoother to many speakers.

No. In standard Spanish, you say:

• cerca de la cueva = near the cave

The preposition after cerca is de, not a.

Other examples:

• cerca de aquí = near here
• cerca del río = near the river

Yes, absolutely. That is very common and natural.

These are all correct:

• ¿Podría usted decirme si...?
• ¿Me podría decir si...?
• ¿Podría decirme si...?

They all mean roughly the same thing. The differences are mostly about style, rhythm, and level of formality.

Because nothing in this sentence requires it.

The clause after si is an indirect yes/no question:

• si ... es fácil perderse ...

That takes the indicative, not the subjunctive, because you are asking for information about a fact or situation.

So:

• si es fácil perderse is correct.

In Spain, a less formal version would often use tú or simply omit the pronoun:

• ¿Podrías decirme si es fácil perderse cerca de la cueva sin brújula?
• ¿Me puedes decir si es fácil perderse cerca de la cueva sin brújula?

Compared with the original:

• ¿Podría usted decirme si sin brújula es fácil perderse cerca de la cueva?

The original sounds polite and formal. A tourist might use it with a stranger, an official, or someone they want to address respectfully.

Brújula is pronounced roughly BROO-hoo-la.

The written accent shows that the stress falls on the first syllable:

• BRÚ-ju-la

Without the accent mark, the stress rules would suggest a different pronunciation, so the accent is necessary.