Edna, I'm sorry that your question wasn't answered in a timely manner. I regret that I can't advise any specific medicines at this time. The cause of the wounds in his ears need to be determined by his vet. For example, are they wounds inflicted by another animal? Are they self-induced by his excoriating his ears by scratching at them? Do they represent skin infection, an allergic dermatitis or neoplasia (cancer)?
Severe halitosis also has a number of possible etiologies - dental abscessation, periodontitis, oral neoplasia, stomatitis (general inflammation of the mouth) - and the odor may be coming up from his stomach as might be seen with acid reflux or gastrointestinal ulceration due to chronic hepatic or renal failure or perhaps advanced diabetes mellitus.
At 13 years of age, he doesn't have the reserve of a much younger cat and so I encourage your having his vet attend to him at your earliest convenience. I would expect a thorough physical exam including diagnostics in the form of blood and urine tests to be performed. Please respond with further questions or concerns if you wish.