This is the 4481st most frequent Japanese word.
始
"始" means "to begin" or "start."
In '始まる' (begins), '始' conveys the starting point of his speaking.
彼の話はいつも始まると止まらない。
Once he begins talking, he never stops.
In this sentence, '始' is used in '始めました' (started), indicating the initiation of an action, specifically beginning a new job.
新しい仕事を始めました。
I have started a new job.
Here, '始' is part of '始まります' (starts), referring to the beginning or commencement of an event or lesson.