A motorcycle IBT (Initial Basic Training) in Ireland is

a mandatory, modular training course for learner riders, designed by the Road Safety Authority (RSA) to teach essential skills and improve safety, covering theory, off-road, and on-road riding, and is required before you can legally ride on public roads or get insurance/tax for a motorcycle. It's broken down into programs depending on the bike category, with instructors issuing a completion certificate after each module or the full course.

See https://www.rsa.ie/ for more information.