Congrats on your pup. One thing I strongly recommend with all my students is to teach the dog its name so that you get instant focus as soon as you call him. This is priority 1 so that if he gets off leash you can call him and get him to come straight back.
I suggest high value treats such as VIP Chicken Chunkers, viennas, cheddar cheese, shredded ham for this as you need to be way more rewarding than if he ignored you.
You also need to socialise the chap with both other dogs and humans. Join a dog club and take him down there to meet and greet people and dogs. Take him to shopping centres and walk around outside the entrance letting him greet people. This is where you can reinforce the sit for the greeting - ie sitting quietly and no jumping up he gets a big jackpot reward.
Be wary of dog parks as they are frequented by some irresponsible people and you do not want your pup to have an unfortunate incident at this most impressionable age.
From an exercise point of view, most Labs love to retreive and to swim so by combining these two you can stand on the bank and throw the ball until he is tired out.
Go to it and keep us posted.
Border River Pet Resort