Okay kiddo, have you ever walked in a line with your friends? And have you ever heard someone say "take two steps to your right" or "take two steps to your left"? Well, that's what we call right and left.
But when we talk about "proper right" and "proper left" we mean the direction which is closest to the object that we're talking about. So, imagine you're standing in front of a statue, and someone tells you to move to the statue's proper right. This means you should move to the right side of the statue from your perspective, but the statue's left side from its own perspective.
It can be a little confusing, but just remember that "proper right" and "proper left" are used when we want to be specific about a direction based on the object's own perspective.