Hi Maureen!
How exciting that you're taking a trip to Dingle.
There are two parking lots in Dingle that are suitable for leaving your car.
There's a paid parking lot in Dingle's marina, which would be a very secure spot to put your car without any worries.
Furthermore, there's a large free public parking lot next to the church on Goatstreet.
If you're planning to book a B&B or hotel in Dingle when you come back to town after your hike, or where you'll be staying before your hike, you could always ask them if you can leave your car there. The Marina Lodge, Benners Hotel, and An Capall Dubh are all lovely places to stay that offer parking to customers.
Have fun!
Alinde