Something you don't know

Alright, listen up, you dummy! The kid in the meme is tryna be all mysterious and stuff. He's sayin' he knows somethin' we don't, then reveals he's not left-handed. It's supposed to be unexpected and stupid, kinda like your jokes. So basically, it's like a dumb surprise that's meant to make you chuckle, even though it's not really funny. Got it, genius?