I don't own a PWD, but I have met a handful and do own a Lagotto Romagnolo, which often comes up as a similar breed and is compared to the PWD quite frequently. I also own an oversized 'mini' poodle I got as a rehome off Craigslist.
My first thought is that I would not expect a PWD to have a 'relaxed GR' or 'chilled out lab' temperament, except maybe in their senior years. They are a breed known for their energy and thrive with regular exercise and activity. The flip side of this is when you have a breed that's called 'active' and 'energetic' and 'intelligent', you likely also have a dog who will absolutely find ways to entertain themselves if they aren't getting the mental and physical stimulation they need. And that self-entertainment is often not ideal - stealing things off countertops and running around with them, getting into coat pockets or backpacks that were left out, 'helpfully' emptying the laundry basket across the living room, chewing or ripping rugs, furniture, their own bedding... you get the idea.
This may never be a problem if your household is active enough and you're providing mental stimulation in the form of training, 'sniffari' walks in new and interesting areas (esp. green or wooded spaces), and enrichment like puzzle feeders, but you definitely want to look at what you'll be doing daily to meet the dog's physical needs. And it really does need to be something where you're out doing it with the dog - even if that means sitting on a chair and throwing a toy to fetch. A dog left to its own devices in a yard, even a large one, isn't really motivated to exercise the way it really needs. Family walks, bike rides, runs, etc. in the countryside sound awesome! The question is whether those are happening regularly multiple times a week, or are they more of a weekly or 'every so often' kind of thing. Play with kids can also be really awesome activity, but of course you can't rely on the kids to be providing for the dog's needs, so you need to be sure you can keep up with that energy when they're busy with school or friends, away at summer camp, etc.
Energetic dogs often need to be taught how to settle in the house. Some people fall into the trap of exercising the dog until it's ready to collapse and sleep for the rest of the day, but only wind up creating an athlete that demands more and more exercise to be satisfied. You can absolutely talk to breeders about what kind of 'off switch' their dogs have at home, but my experience with my Lagotto is that even as a puppy he needed enforced naptime in his pen or he would become overtired, wild, and cranky (just like some toddlers do when they need a nap). Even now (he'll be two in a few months, so still solidly an adolescent) we sometimes have to enforce calm breaks, because he and my older dog will work each other up and get way overstimulated to the point where they start snarking at each other. We also do regular relaxation/zen/calm training games to build his skills at settling and self-entertaining in calm, appropriate ways (like an appropriate chew toy) when we can't be engaging with him.
In this way he was a VERY different puppy than my poodle was. And still is a very different adolescent. Sam (the poodle) was always very good at settling and napping on his own, though he'd still get worked up sometimes. He's satisfied with much less activity or training, and tolerates periods of time where we can't give him as much activity or attention much better (eg one of us is sick or the weather is extremely nasty or dangerous). All puppies are going to be wild, but not all of them are going to require enforced nap breaks, figure out how to walk their pen across the living room, try to climb the shelving, steal gravel from outside so they can trade it for a treat, etc.
Lagotto also need very careful, high-quality socialization. They're a bit of a sensitive breed and naturally more suspicious of new things or changes in their environment. I can't speak for the PWD entirely, but by reputation they're also a little more sensitive in this regard than, say, a poodle. If you haven't socialized a puppy before, it can be challenging to know what 'good' and 'bad' socialization looks like. In my case, I thought 'good' socialization was having my poodle meet every dog on-leash and interact with them... and I wound up with a dog who's extremely frustrated when he can't approach on-leash dogs and it's turned into a seriously stressful event for him to be around strange dogs at all while he's leashed. A socialization program should focus more on the puppy seeing, hearing, and smelling a wide variety of things and learning to experience things like people and other dogs being around without having to interact with them. Interactions should be much more selective and only occur between people and dogs you know will be good and respectful with the puppy, and be kept short and as positive as possible. No letting a puppy loose in a 'puppy party' with ten other dogs to let them work things out for themselves (even though there absolutely are trainers who do this still). No letting strangers grab or pick up your puppy. No forcing the puppy to approach or interact things they're actively frightened by (but observing them from a distance where your puppy is comfortable and/or letting puppy hang back while you go up and interact with the thing to show it's not scary can be good).
I feel like I'm rambling quite a bit, so I'm going to stop here to say a brief piece about poodles. They're absolutely wonderful dogs, and - in my opinion - quite underappreciated as a wonderful family and companion breed. One of the big advantages with poodles is that they're so popular in comparison with other water dogs, like the PWD, that you can easily find a breeder whose breeding goals align with your family's needs. While a poodle from a breeder who's focused on producing sport or hunting dogs may have a lot of those higher energy needs and intensity that I described above, there's tons of breeders who are focused more on a solid, all-round companion. Their dogs might do therapy work (visiting hospitals and care homes), be service or assistance dogs, and they'll have lots of households you can reach out to and hear how their puppies fit in to their family life, etc. Locally, a standard poodle does a reading program at the library for kids, where kids who aren't super confident with their reading skills can read to him and he'll follow their finger with his nose along the page. His predecessor was also a standard poodle. And you absolutely don't need to keep them in an extreme show cut, if you're hoping for a more rugged look.
Thee high-energy, "needs a job" type breeds, when their needs are met, (as it seems your pup's will be, for sure) are the best dogs to have- it's so rewarding.
