Okay kiddo, have you ever seen the TV show called Seinfeld? Well, there's one episode of Seinfeld where the main character named Jerry, has a friend named Elaine. She needs a date to go to a wedding, but the guy she wants to bring as her date is already going to be out of town. So she asks Jerry if he knows anyone who can go with her instead.
Now, Jerry knows a guy who looks almost exactly like him, named Kenny. Kenny is an actor who works as a "stand-in" on movie sets, which means he stands in for the real actor while they adjust the camera and lights, and then the real actor comes in to do the scene.
Jerry tells Elaine that Kenny is technically him, but just in a different body. And since Kenny looks almost exactly like Jerry, he can stand in for him, as if he were Jerry himself. So he can be Elaine's date and nobody will even know the difference.
But when Elaine and Kenny get to the wedding, things start to get a little weird. A woman at the wedding sees Kenny and thinks he's Jerry, so she starts flirting with him. And then Elaine realizes that she's actually more attracted to Kenny than she is to Jerry.
So the whole episode is about how Kenny the stand-in looks so much like Jerry that he can fool people into thinking he's him, but also how he's different enough that he creates some unexpected issues. But in the end, everything works out okay and Elaine ends up having fun at the wedding with Kenny.