A certification is a floor, not a ceiling. Passing the lifeguard course just means you’re allowed to start learning.

A qualification proves you have reached the minimum somebody decided was safe. It does not mean you are good, and the distance between the certificate and real competence is where most of the learning actually sits. Treating the paper as a finish line is how people stay beginners for years while technically being qualified. The course gets you through the door; the shifts are the education.

Whatever you have just passed, pick the part you scraped and work on it on purpose. Ask somebody experienced what new people usually get wrong. Watch for that in yourself for a month rather than assuming you are past it.