A dog owner is responsible for their pet in public places, so if your dog misbehaves you could be in trouble. A poorly trained dog can also be a danger to himself. Imagine the consequences if your dog ignores you and runs across a busy road. In order to have the perfect pet you will need to start training when your dog is very young. The rewards of this are clear - there is perhaps no greater pleasure than owning a well-behaved dog.
Puppies that have not had a good start in life and have not been exposed to lots of novel experiences are often poorly socialised. These puppies may go on to develop behavioural problems in later life. Many undesirable behavioural traits can be traced back to inappropriate experiences during early development.
Contact your vet for advice on where to get training for your puppy. If your pet is showing any undesirable behaviour then you should discuss this with your vet at the first opportunity. It is always much easier to resolve behavioural problems early in their development before they have become ingrained habits.