Hey Jonathan,
As the others have pointed out, just let your puppy be a puppy for now.
1) this exploring new stuff and confidence-building is absolutely essential to end up with a calm and happy adult dog, not a nervous jumpy wreck.
2) at that age, puppies don't have the maturity and focus to ignore distractions and stick to your side. You will just cause him a great deal of stress and anxiety if you don't allow him to express his curiosity and playfulness.
Remember, it's easy to put a harsh training collar on a dog (or puppy) and jerk it around into submission. Any moron off the street can do that.
It takes a lot more skill and intelligence to figure out ways to get your puppy to do what you want without applying force
It's often harder than it seems but by thinking about how you can solve a problem and experimenting, you acquire training skills.
It's your chance to outsmart Konichiwa!
Let him explore, find somewhere where he can maybe have a bit more freedom (dragging a long line so he's still within your physical control if you need it, but not having to walk on a 6-foot leash). When you want to teach him to come to you, you have to figure out a way to make yourself more interesting than whatever he's doing.
What Carol said (on another thread) works really well!
Basically you have to make a complete fool of yourself. Speak in a really excited high-pitched voice, clap your hands, jump around, run backwards (away from the puppy), roll a toy around on the ground, bounce a ball around etc.
That should get his attention! When he does come to you, give him a treat and act like he just did the most amazing thing in the world.
Puppies (and dogs) respond to that.
Yes you will look and sound completely crazy to everyone except your puppy. He will understand and that's what counts.
You can teach him to heel already if you want to (informal heel, not competition heeling). In fact, you can work on the sit, down, come, whatever you want to, as long as it's all a game for the puppy and you don't try to force him to do anything.
Use really good food to get him to walk beside you while you say "heel".
If possible, let him take the food from your mouth. This will teach him to watch your face. This works pays off when he's older and you want his focus on you.
Good luck, it sounds like you're really enjoying the baby!
Haha, sorry about the toys. I guess it's up to you to put some excitement into the toys to stimulate his prey drive!
A little warning about letting dogs play with sticks - they can get injured doing this. Dogs can stab themselves when running with a stick (they can even puncture their throat) and the results are not pretty.
Even if the dog doesn't run with the stick, the splinters can injure the dog's gums and make his mouth bleed. Speaking from personal experience here!!
I discouraged my young male from picking up sticks when he was 6 months old or so after he got splinters in his mouth and bled for several minutes (scaring me half to death though he didn't seem to notice).
I just told him NO, LEAVE IT every time he went for a stick (and he was stick-obsessed as a puppy!!) and redirected him to a toy instead. Once he realized that I wouldn't play with sticks, he learned to obsessively love his orbee balls.
Now he doesn't even look at sticks anymore and it's a relief!