If your dog hunts pheasants, it’ll be different but he’ll hunt grouse and would be good to have along. As long as you have him under control and not flushing birds out of range, he’ll be really helpful to find downed birds so definitely bring the dog. Its not “textbook” but Ive hunted mainly grouse with labs for decades and it can be very effective, so hour chessie should be fine. The pointing dog folks all seem to gravitate to bigger, flatter terrain with big growing-up clearcuts. With my labs Ive had better luck in more linear cover (cut or vegetation edges, swamp edges, stream bottoms, twitch trails grown up in whips, etc) since the dog and I are covering a +\- 40-yard wide strip, not the 100+ wide strip a bigger-running dog will. Both can be very effective but they require approaching things a little differently and maybe a different set of eyes to put yourself where you’ll be most effective given the tools at your disposal. Either way, young forest with good ground cover that’s mixed with some evergreens is what you are after, you’ll get a feel for it after a bit. It’s fun though, and can be tough shooting. If it’s a pheasant dog already, once your dog figures out these new birds are quarry he’ll get birdy and indicate he’s on a bird before it goes up 9 times out of 10, so you are at a huge advantage having a dog. You just have to learn to recognize what it looks like when he’s on a bird via his pace, if he gets helicopter-tail, etc. hardest part is maintaining visibility to see when dog is on a bird as well as for safety, so it can be helpful to put some orange on the dog (some people use a bell, I like to be quiet), and make sure you and anyone you hunt with never shoot low birds and keeps in either visual or sound touch with each other so in a “snap” moment when a bird goes up you already know where it’s safe to shoot. If you shoot, follow up with the dog, you might be surprised how many “darn, totally missed that one” birds it brings back.
Grouse are easy to kill, a standard target load of 7/8oz or 1oz of 7.5’s is plenty, and a skeet choke—or anything from cylinder to IC—is perfect.
Edit: in most (all?) of the states ive hunted in its illegal to shoot from within a certain distance (10’ or 25’ as well as any shooting over a road) a public roadway, regardless of whether its paved or a 3rd or 4th class road. So check regs. Lots of people do it, but it is not legal at least everywhere im familiar with. Theres lots of ways to hunt them, but if you are in the upper midwest the above hunting clearcut thickets with dog and on foot is what “grouse hunting” means, at least to me, so while youre there you should dabble in it at least.