IN HERE typically refers to an indoor location that you are at right now. For example, if you're inside a kitchen, you might say, "It's hot in here."
OUT HERE typically refers to an outdoor location that you are at right now. For example, if you're on a beach, you might say, "It's peaceful out here."
OUT THERE typically refers to an outdoor location that you are NOT at right now. For example, if you're currently inside a house, but you are talking about a beach , you might say, "It's crowded out there."
I hope this helps. Good luck!