Am I able to buy medications for my dog? He is running a fever.

If it's a prescribed medication, you need to have your animal examined by their qualified staff and have them prescribe it. Others they may have on hand. Best to call them.

They have vets which can provide a proper diagnosis and provide the medication

Where can I get it? Does it require a prescription?

Yes

They sell medicine yes as to the specifics you may be needing you will likely have to call them.