Pour que (so that, in order that) is always followed by Le Subjonctif Présent (subjunctive mood)

Bonjour CrystalMaiden !

Afin que is not so much rarer as more elegant and high standard than pour que.

But you can use it as much as you like :)

Bonjour Shruti !

Here, le refers to what has been said previously:

-> I'm telling you [it] so that you're not surprised.

In French, when you use the verb dire, you will usually need to add "what" you're saying, either fully, or with a reminder pronoun like in this sentence.

See also:
https://progress.lawlessfrench.com/revision/grammar/use-le-or-l-to-refer-to-previously-mentioned-complete-ideas

Bonne journée !

Bonjour Shivani !

Excellent question!
Technically, you are correct: amener is for people whereas apporter is for things.
Unfortunately, this is one of these very frequent mistakes most French natives make, including myself :)
I've now corrected this example :)

Merci et à bientôt !

Merci beaucoup Aurélie !

Bonjour Jennifer,
I am unable to locate the phrase in the lesson for your comparative example: I am calling you so that you can come
For your second example, this is how I would/could state it:
Je vous appelle pour que vous pouvez venir. (this is technically incorrect)
For the first part of the example, the use of le subjonctif présent is correct.
One thing to keep in mind is this:
I think that the examples given are for demonstration of the grammar point. Here is another translation for the first example:
«Je vous remets les clés de sorte que vous pussiez entrer»
As one can readily see, this phrase also uses le subjonctif.
Having said that, there are phrase constructs that allow for not using le subjonctif, here is one link:
http://www.laits.utexas.edu/tex/gr/tas8.html
There are some schools of thought that teach this method. For myself, I prefer to learn le subjonctif usage correctly.
Bonne chance dans vos études en français.
Ron

The full sentences given were as follows:-
Je t'appelle pour que tu viennes - I'm calling you so you can come (in one of the quizes) and Je te donne mes clés pour que tu puisses entrer - I'm giving you my keys so that you may come in - from the pour que lesson. I just wondered why the first example did not use puisses venir which would have followed what the second example did.

Bonjour Silken !

It depends on the verb, but all regular verbs and many irregular ones follow this pattern: https://www.french-test.com/revision/grammar/conjugate-regular-verbs-in-le-subjonctif-present-the-subjunctive-mood