Neutering is a guarantee of nothing other than stopping the dog's ability to breed. It does not typically result in any significant behavioral changes.
Your dog is still a puppy, and they are generally higher energy and lack the off switch of adults, but a mix of those two breeds is likely to be on the higher end of the energy spectrum and will likely need more than two twenty-minute walks a day. I mean, you can probably get away with that, but you would have to supplement it with training sessions, or perhaps a game of fetch, something that lets him run and exert some energy.
Your dog is still a puppy, and they are generally higher energy and lack the off switch of adults, but a mix of those two breeds is likely to be on the higher end of the energy spectrum and will likely need more than two twenty-minute walks a day. I mean, you can probably get away with that, but you would have to supplement it with training sessions, or perhaps a game of fetch, something that lets him run and exert some energy.