Another session of Virtual Beer School (https://virtualbeerschool.com/) begins on Wednesday.
This is a Cicerone exam prep course.
It covers not just the science of brewing + beer styles, but beer + food pairings + serving beer, too.
It is wider knowledge than most homebrewers need, but if you're serious about beer, Cicerone (https://www.cicerone.org/us-en/cicerone-certification-levels) is the most rigorous qualification out there.
This course is also great value for money, especially for anyone new to beer styles.
Sign up here: Virtual Beer School (https://virtualbeerschool.com/)