Bonjour Gabriel,
It’s fantastic that you’re considering Ireland for volunteering experience!
As you said, a youth hostel is a great idea—platforms like
Workaway or our
accommodation/hostel search tool can help you find options. Were you set on an area in particular?
You could also explore eco-projects or farm work like
WWOOF Ireland, this is something I've recommended in the past (even though I haven't done it myself) and you could end up in more rural areas than hostels, if that's what you fancy.
Let me know if I can help further or if you have other practical questions (travel, things to see in Ireland, you name it!)
A bientôt,
Antoine