及ぼす
およぼす · oyobosu · JLPT N3 · verb-godan
to cause
及ぶ oyobu = to reach; 及ぼす oyobosu = to make something reach
The -bu to -bosu switch turns reach into make reach. If you exert influence, your influence reaches other people. You will usually see it in 影響を及ぼす, to exert an influence on, or 害を及ぼす, to cause harm.
及 — hand 又 reaching person 人
Originally a pictograph showing a hand (又) catching or reaching a person from behind, depicting the act of catching up to someone. The core meaning 'to reach' or 'to catch up to' extended to 'and' (reaching/including more items) and 'in time for'. Modern form simplifies the person and hand into connected strokes.