He’s been to the vet already twice. They prescribed Cephalexin, Doxycycline, Carprofen, Ofloxacin, and eye drops. But I haven’t seen much difference. Does anyone know what it is?
If your vet is not taking this seriously enough, or doesn't know what it is, you need to find a new one. If your vet doesn't have the skill, you need a new one. This looks serious. I haven't finished my degree yet, so I'm really not able to do any sort of full diagnosis, but that is a mass that could,
potentially, need to be surgically removed. It may even be cancerous. Best case scenario, it doesn't even need surgery. But he could- I'm definitely
not saying this is the most likely outcome, especially since I haven't seen it- but he could end up having to have surgery and have part of his eye removed, or maybe even, in an extreme case, his entire eye removed. Again, without seeing it in person, can't say. It may be Ocular Melanoma... if that's the case, either Uveal or Limbal Melanoma. The more common of the two is Uveal, which is something like 80% benign (non-cancerous). He could be looking at cryotherapy and laser therapy, in addition to surgery.
Still. It needs to be looked at by a vet. If your current vet's treatment has not worked, and he doesn't know what to do next, take your pup to another vet. But do whatever your current vet says. Only if that treatment does not work after the time period your vet specified should you begin looking for other solutions. The medication will work only if applied consistently and in accordance with your vet's instructions.
From what you said your vet prescribed, it seems like he thinks it is a bacterial infection. Does he have a "next step" plan for what to do if treating it as an infection doesn't work? Has he expressed any concern that it could be mass not caused by bacteria? Did your dog get into something or injure is eye or face prior to when these symptoms appeared? Be sure to ask lots of questions.