Learn Farsi: نابیناها از این دستگاه استفاده می‌کنند.

The word nâbinâ is an adjective meaning "blind". By attaching the plural suffix -hâ, it becomes a noun referring to the whole group: nâbinâhâ (blind people or the blind). This is a very common way to turn adjectives into nouns for groups of people.

Is there a literal meaning to the parts of the word nâbinâ?

Yes. It is made of the negative prefix nâ- (un- or non-) and binâ (seeing, sighted). So it literally translates to "un-seeing".

Why is the preposition az (from) used before in dastgâh (this machine)?

The Farsi verb for "to use" is the compound verb estefâdeh kardan. When you mention the object being used, you must introduce it with the preposition az. In Farsi, you literally make use "from" something.

Would it be wrong to use the singular verb mikonad here instead of the plural mikonand?

Yes, it would be wrong. Because nâbinâhâ refers to human beings, the verb must match and be plural. If the plural subject were non-human (like machines), you could use a singular verb, but human groups always take a plural verb.