This is the 55th most frequent Armenian word.
նա
"He" or "she" (third-person singular pronoun).
In this sentence, 'նա' is used as a third-person singular pronoun referring to either a male or female subject, depending on the context, as Armenian does not distinguish gender for this pronoun.
Նա գնաց դպրոց։
He/She went to school.
In this usage, 'նրա' is the possessive form of 'նա', which indicates that the table belongs to the person referred to.
Գիրքը նրա սեղանին էր։
The book was on his/her table.
Here, 'նա' serves as the subject pronoun indicating the individual who likes being in the kitchen, again without specifying gender.