lighting – What exactly is causing the quality difference between these two photographs?

Here is a photo of 2 individuals: my friend and a male model (right). Both of them are clicked in daylight. I get it that the background on the left picture is very bad but that cannot be the only reason why there’s such a big quality difference between these two! The costume? Or is it the camera?

PS: I’m an absolute newbie to the world of photography so PLEASE guide me!

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