I had a very rambunctious Doberman puppy. I never had to harshly reprimand him and he is a lovely, well mannered, well trained adult dog now. Reprimanding (scolding) a dog for being a dog is confusing and teaches your dog to distrust you. He has no sense of our morals or values. He can learn all the things you want by showing him alternative behaviors to behaviors you don't want. If he's jumping up on you, it is because he is seeking attention. Attention then, is the reinforcer. So, if you do not give any attention, zero, zippo, none, not good, not bad, not a word or a look...nothing, he will get back down because he's not getting what he wants. He'll probably sit because often when dogs are in question, they plop into a sit. Wait for that. THEN squat down and lavish him with attention and a treat. It won't take long if you're consistant and everyone who interacts with him is consistant to choose the behavior you want....a sit for a greeting. It is cruel to punish a dog for greeting you the only way he knows how. It's like someone reprimanding you for wanting to shake hands.
The same thing goes for chewing. Keep your valuables put away. Puppy proof your house. The more chance for your pup to be reinforced by chewing your good stuff, the more the behavior will continue. Redyre has a wonderful sticky up on having a toy box for your dog. Read that for good, solid training advice.
In general, distract, give alternative behaviors, preferable intercepting the unwanted behavior before it happens.... reinforce those, obedience train, exercise without being excessive to hurt the bones and joints, patience, consistancy, kindness and an understanding of how dogs learn and process information. They do not understand aversive punishment from primates. (us)
I do not recommend a dog park for a very young puppy. I'm not a fan of them at all, but your puppy needs to be fully vaccinated and even then, he will be very vulnerable to who knows what. There are sometimes aggressive dogs and one frightening situation...just one is all it takes to ruin your dog's sociailzation program. It is far better to enroll in a puppy kindergarten class with a reputable trainer who uses gentle, positive reinforcment methods. It is a very good way to socialize your puppy because it's controlled and they're all puppies. If you have friends with friendly adult dogs who are healthy, you could try getting together with one of them. Just be sure the adult dog is exceptionally friendly and tolerant of puppies. A dog park is definitetly not a safe place for a little puppy.