There is often confusion about can/could, will/would. Sometimes students learn in school that could and would are more formal or more polite than can and will.
Note: This may be true when you are requesting something, but in IELTS speaking and writing you're usually using can and will to communicate possibility or ability rather than to make a request.
In this case there is a strong possibility (almost 100%) that I will see my friend's photos on Facebook, and so it is more appropriate to use can.
Let's imagine a similar situation where there is no possibility:
Here the writer clearly does not have an Internet connection and so there is no possibility of him seeing his friend's photos on Facebook. Notice that in this example could is part of a structure called second conditional:
If + subj + V2 + ',' + subj + could/would + V1
In the second conditional the situation you are describing is unlikely:
Second conditional - an unlikely situation - is by far the most common context for could and would.
Indonesian students tend to overuse will because they want to translate akan. But will is not used in English as much as akan is used in Indonesian. Actually there are generally only three situations where will is suitable:
First conditional - a situation that is highly possible:
Habits (often annoying habits), and Routines:
It's unusual to talk about past abilities, because once you acquire an ability, for example the ability to swim, you rarely lose that ability. It would be ridiculous, for example, to write:
We generally only lose this kind of ability when something terrible happens to us:
On the other hand ability can sometimes be a matter of degree. For example we can talk about partial ability, and about changes in our level of ability:
Most of the time when we talk about ability we use can - present tense - because, most of the time, we're making a claim that is true now.
Next time you speak or write could or would stop and think. You probably should be writing can or will!