Aquí means here. It sets the location first:
Spanish often puts words like aquí, ahora, hoy, etc. at the start of the sentence for emphasis or to set the scene.
You could also say:
That means basically the same thing, but starting with Aquí puts a little more focus on the place.
Because Spanish often omits subject pronouns when the verb already shows who the subject is.
So:
You could say yo te llamaré, but that would usually add emphasis, for example:
Así que means so, therefore, or so then.
It connects the two ideas:
It is very common in everyday Spanish.
Similar connectors include:
But así que is a very natural choice here.
Te llamaré is the simple future tense: I will call you.
It fits well because the speaker is talking about something they will do later.
Compare:
In Spain, all three can be heard, but te llamaré más tarde is a very normal and clear way to express future intention.
Te means you as an object: I will call you.
In Spanish, object pronouns often go before a conjugated verb:
Other examples:
But with an infinitive or gerund, pronouns can attach to the end:
In this sentence, the verb is conjugated (llamaré), so te goes before it.
The accent mark in llamaré shows where the stress goes: lla-ma-RÉ.
It also helps distinguish the future-tense ending -é.
Compare:
Spanish accent marks are very important because they can:
They have accent marks for different reasons:
This is an important difference:
So:
Yes, literally it does, but idiomatically it means later.
This is a very common Spanish expression:
It works like English even if the literal structure looks a bit different.
Yes. In many situations, luego also means later.
So these are both possible:
In Spain, both are common. Very generally:
The difference is small here.
Both are natural, but they focus on slightly different things.
In real life, both are very common in Spain. The version in your sentence sounds especially natural if the speaker is explaining why they cannot call right now from that location.
In most of Spain, ll is pronounced like y in English yes, so llamaré sounds roughly like ya-ma-RÉ.
A few notes:
So for most learners of Spain Spanish, pronouncing llamaré like yamaré is perfectly fine.