Socialising a dog doesn't mean meet as many people, animals or obstacles as possible and force them to interact.
It means socialising them well, so they are a confident around a variety of people, dogs, animals and other objects and vehicles etc. Don't force them, go at their pace, be mindful of their body language! What might be a silly thing to you, might be scary to a little puppy.
When your puppy is meeting new people and animals it is important, that all experiences are a good one, so the dog doesn't grow up with negative feelings towards that item or person.
If your puppy hasn't experienced or met anything by 6 months, it will automatically become a potentially 'scary object', so it is important to always go at your puppy's pace, why not just sit back on a quiet road and both of you can relax and take in the surroundings? This gives your puppy chance to observe things from a safe distance and realise things aren't as scary as they first might appear.
Remember just because they live with a dog, it doesn't mean they will be socialised with all dogs, it is important to continue meeting a variety of different dogs right into their adult hood. If a child only met one other person in its how life, would you say this child will grow up well socialised?
Socialisation, if done properly prevents a lot of unwanted behaviour later on.
Your puppy relies on you for safety, so start building that strong bond of love and trust from the start and you'll have a strong relationship like no other.