
You will need to take him to training classes and socialise him well with other dogs and people of all sorts.
The 'window of socialisation' closes at about 16 weeks; until then you need to ensure he's met (and is comfortable and not frightened by) as many experiences as possible. Old people, children, trucks, cars, trains, cows, horses, crowds, cats, bicycles, people in hats, people with sticks, people in wheelchairs, baby buggies ... anything you can think of!
If you teach him that Life is to be trusted then he'll be a safe dog. Dog's behaviour generally reflects the quality of their upbringing - some dogs are more difficult than others (they all have individual personalities, just as people do) but if their owner works harder with them then there is unlikely to be a problem.