個 is built from the 亻 (person (left)), 口, and 古 components.
It reads コ like 古, as do 故, 固, 居, and 湖 — learn 古 once and the family's reading comes with it.
A common word using 個 is ～個 (～こ), meaning “counter for small items (e.g., fruits, cups)”.
Don't confuse it with 故, 枯, 固, and 湖.
