Attached To
Belong To
noun, する verb, の adjective
A place where something belongs is where it is attached. It's where it's attached to. It belong(s) to that place.
しょぞく
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
所属部署に病欠のための診断書を提出しておいた方がいいよ。
You should turn in doctor’s notes for sick days to your own department.