Ako stignemo prekasno, prenoćit ćemo u hotelu pokraj kolodvora.

Stignemo is the 1st person plural present of stići = to arrive / to make it.

After ako (if), Croatian normally uses the present tense for a future possibility:

Ako stignemo prekasno... = If we arrive too late...

That is similar to English, where you also usually say If we arrive late, not If we will arrive late.

Also, stići is a perfective verb, so its present form often refers to a future completed event in clauses like this.

Prekasno means too late, not just late.

• kasno = late
• prekasno = too late

The prefix pre- often adds the idea of too much or excessively:

• preskupo = too expensive
• prebrzo = too fast
• prekasno = too late

Prenoćiti means to spend the night somewhere or to stay overnight.

So prenoćit ćemo does not just mean we will stay in a general sense. It specifically means we will stay there for the night.

That makes it a very natural verb in a sentence about arriving too late and needing a hotel.

This is the standard way Croatian writes the future tense when the auxiliary comes after the infinitive.

The verb is:

• prenoćiti = infinitive

The future auxiliary is:

• ćemo = we will

When ćemo comes after the infinitive, the final -i of the infinitive is dropped in writing:

• prenoćiti + ćemo → prenoćit ćemo

So prenoćit ćemo is correct standard Croatian.

Compare:

• Prenoćit ćemo u hotelu.
• Mi ćemo prenoćiti u hotelu.

Both are correct, but the spelling changes depending on where ćemo is placed.

Because this sentence expresses location, not movement toward a place.

In Croatian:

• u + locative = in / at a place
• u + accusative = into / to a place

Here the meaning is we will stay overnight in the hotel, so Croatian uses the locative:

• u hotelu = in the hotel / at the hotel

If the meaning were movement into the hotel, you could have u hotel.

Pokraj means beside, next to, or near.

It takes the genitive case, so kolodvor changes to kolodvora:

• kolodvor = station
• pokraj kolodvora = beside / near the station

So the ending -a in kolodvora is there because pokraj requires the genitive.

By itself, kolodvor can mean a station/terminal in a general transport sense, and the exact meaning depends on context.

If Croatian wants to be more specific, it can say:

• željeznički kolodvor = railway station
• autobusni kolodvor = bus station

In a sentence like this, kolodvor often just means the station that is relevant in the situation.

Yes. Croatian word order is fairly flexible.

This sentence can also be written as:

Prenoćit ćemo u hotelu pokraj kolodvora ako stignemo prekasno.

Both versions are correct. The difference is mostly about focus and style:

• Ako stignemo prekasno, ... puts the condition first
• Prenoćit ćemo ... ako stignemo prekasno. starts with the result

The version with ako first is very natural when you want to introduce the condition before giving the consequence.

Because the sentence starts with a subordinate if-clause:

• Ako stignemo prekasno = subordinate clause
• prenoćit ćemo u hotelu pokraj kolodvora = main clause

When that kind of clause comes first, Croatian normally separates it with a comma.

If you reverse the order, the comma is often omitted:

Prenoćit ćemo u hotelu pokraj kolodvora ako stignemo prekasno.

The sound ć is a soft consonant that English does not have exactly.

A rough approximation is a very soft ty or a soft ch sound. It is softer than č, which sounds more like the ch in church.

So:

• ć = softer
• č = harder

In ćemo, try not to make it a strong English ch. A learner approximation is fine at first, but it should sound softer than čemo would.

It can feel a bit irregular to English speakers because the infinitive is stići, but the present stem is stign-:

• stići = infinitive
• stignem = I arrive / I make it
• stignemo = we arrive / we make it

So yes, it is one of those verbs where the present-tense stem is not identical to the infinitive stem. That is something you simply need to learn with the verb.