Fo Día / Fó / Día do bethu
Irish Gaelic has seanchara (old friend): the closest Scottish Gaelic found is seann-eòlach (old acquaintance)
"Hello" in English: "Hello". In Welsh: "Was Hael". In Italian: "Salve". Can't help you with Irish (Gaelic) I'm afraid.
how old are you
I think you mean Hello it's Dia duit
The native Irish name Brónach is considered an equivalent.Dia duit, a Bhrónaigh.
Gaiscíoch SíochánaLaoch SíochánaThat's modern Irish not Old Irish.
"Dia dhaoibh" (pronounced: deea yeev)
"Cén aois tú?" in Irish.
The most common language in Ireland is English, so "Hello" is used. In the Irish language, you would say "Dia dhuit", (pronounced: Dee a Gwit) which is a greeting that literally means "God be with you."
Dia dhaoibh a chlann (hello my children) le grá ó mham (love mum)
If by 'Ancient Irish' you mean "Old Irish" it is "teg, tech". Modern Irish is tigh/teach.
God be with you: Dia duit May God be with you too: Dia is muire duit That is also what people say to say hello in Irish if you say "Dia duit" the other person should say "Dia is muire duit"