Thanks! I'm just excited to see people learning Irish and want to help anyway I can.
"Na" is for when something is plural, for example "Na mná" (The women). "An" is for when something is singular, for example "An bhean" (The woman).
all the plurals usually relate to the singulars yet the plural for woman does not e.g. fear fir yet bean and mna
it's ná with a fada, so it'll sound different than na the article.
That said, in Connacht and Ulster that /n/ has become an /r/, so it's pronounced as if it were written mrá