It's the best place to start if you want a sense of what the world is about.
World of Warcraft's story and mythology are daunting and dense, but are worth immersing yourself in if you love high fantasy with a little bit of campiness to it. Still, unless you played the earlier real-time strategy games and read their manuals like the gospel, you probably don't really know what's happening and why. For that, YouTuber Nobbel87 is the person to turn to. His 41-minute long video covers the entirety of World of Warcraft's lore and is a lot of fun to watch. It's the best place to start if you want a sense of what the world is about.