I've had three male cats that I got neutered. None of them had or needed a cone. I don't remember any of them particularly interested in bothering the surgical site either. Depending on how long after surgery the cat comes home, he may be sleepy and probably not very interested in food. If he does seem hungry, don't let him eat much at first. Give a little food at intervals to see if he keeps it down. He probably will have been given a pain injection that may affect how he feels for a bit.
Male neutering is much easier than female and is basically a very quick and easy surgery. I never had any complications from any of mine.
Unless he's having other things done while under anesthesia, he should be fine. Just keep an eye on him and if you feel there is a problem, call your vet. My vets always call me the following day to see how my animals are doing so I can ask any questions I might have.
Your little guy should do just fine!