Weird stuff in one of my cats ear

Hello, does anyone know what this possibly might be on one of my cats ears? recently my cat has been sick, we first thought it was an upper respiratory infection sinxe he shows signs of that, but now were a bit more worried. We don't have any money for vets and would like to know if this is treatable at home, I barely noticed this a couple of min ago and don't really know how long he's had it for since we hadn't noticed it. The last picture in the post is his normal ear/side that doesn't have whatever his other side does have. It seems like hair is missing and some of it seems like it is wetish.