If you specifically need the 1998 version (v1.0 or v1.05) for speedrunning or specific modding, you might turn to torrent sites or "abandonware" archives.
In this guide, we’ll walk you through how to access the game safely, why the ISO format matters, and the best ways to play in the modern era. Why Search for a StarCraft: Brood War ISO? Starcraft Brood War Download Torent Iso