Anyone with experience volunteering as a first responder in Dublin?

I was looking into first aid classes and found some old threads on here where people suggested volunteering for organisations which would provide the training for free (IRC, CFR, order of Malta etc…)
However, I would like to have an idea of the time commitment and the expectations on the type of person that is needed for the job. I would be very interested to volunteer, just need to see how it would work around a full time job.
If anyone has firsthand experience or any first aid course suggestions I’d highly appreciate it. Most of the non profit organisations have broken links and/or not enough information on their website. FYI I am not Irish (not sure if this changes things)
Thanks!