Zeus’s father was Cronus. Cronus swallowed Zues’s brothers and sister. He planned on swallowing Zues when he was born. But Rhea hid the newborn in a cave on Mount Dicte in Crete. Zeus caused Cronus to vomit up his sisters and brothers. All together they killed him and the titans.
For example, Zeus killed his father and other titans and sent most of them to hades.
In the texts it says, “Having vanquished his father and the other Titans, Zeus imprisoned most of them in the underworld of Tartarus” (mythweb).