That is a very natural question.
Gemeenskap is grammatically singular: the community. But its meaning refers to a group of people. Because of that, Afrikaans can use mekaar to express what the people within that group do to one another.
So the sentence is understood as:
This is about collective meaning, not strict English-style agreement.
Not if you want the meaning each other.
So these are different:
The second sentence means the community is helping some other people, not helping one another.
Because the main verb here is help, not to be.
In English, some learners expect an extra verb because English often uses helper verbs in some structures. But here Afrikaans works just like English in a simple present sentence:
No extra is/are is needed.
Yes. Gemeenskap can mean community in a broad sense.
Depending on context, it can refer to:
So the sentence could describe many kinds of communities, not just people living in one place.
A rough English-friendly guide is:
A few helpful notes:
Pronunciation varies somewhat by accent, but that rough guide will help you get close.
In normal standard Afrikaans, you usually keep die if you mean the community.
So the standard form is:
Without die, gemeenskap would sound less like a normal complete noun phrase in this sentence. You might see article dropping in headlines, labels, or certain special styles, but for ordinary sentence practice, keep die.
It is understandable and natural enough, especially in learner material.
A very literal gloss is:
In more natural English, we might often say:
But the Afrikaans sentence itself is a normal compact way to express that idea.