Lovely to hear that you'll be spending time in Ireland in July, Kenmare is a great place to visit.
Public transport is one of the best ways to travel around the island of Ireland! Our general information page on public transport
will give you a good idea of what is available for your trip, and I would advise you to download the Journey Planner app, as the trip between Dublin and Kenmare is quite a long one.
Your travel times would depend on what time you arrive in Dublin, but generally speaking the trip takes between 6-8 hours, with 2 -3 transfers along the way.
Have you planned your itinerary for the visit already? Kenmare is lovely, and the area has some wonderful things to see and do as well, for instance Kenmare Farmer's Market
Wishing you a wonderful day,