"It is a general question."
Translation:Είναι μία γενική ερώτηση.
Yes, it could be skipped. Thank you for commenting, I added it as an alternative translation. ^.^
Because ερώτηση is feminine, so you have to use the feminine indefinite article μια (or μία, though that may be more commonly used for the numeral "one").
ένα would be used for neuter nouns.