Study hours are the hours of volunteer activities. There is a youth volunteer club at the school level. In other words, all students are default members. He will send everyone a volunteer card with a page to record your volunteer activities. Generally speaking, a volunteer activity lasts two to four hours. The more activities you take part in, the more time you record.
Basically, it is not very useful, but there are still some. Applying for any professional title does not necessarily require working hours.