For this, you will need Form E111 (which may be valid for a limited period only), which you can get from the institution with which you or your parents are insured.
Le tacú leis an gcóras seo - le heisceacht amháin i gcás na hailtireachta - tá bunleibhéal comhoirdnithe ar siúl ó thaobh traenála sna gairmeacha sin.