The Gros Morne National Park is located about 1 1/2 hour west of Deer Lake, the closest airport and serviced by the larger Canadian airlines. Norris Point and Rocky Harbour are the best location for your accomodation. You can already see from here one of the main attractions, the Tablelands.
On Day one take a drive to the Western Brook Pond, north of Norris Point. You will have to park your car and hike about 45 minutes to the lake, what isa nice easy hike, partly on a boardwalk with great scenerie and you might get rewarded with a moose sight.
Once you reached the lake, you can go on a 2 hour tour on the lake through a fjord-like scenerie, but book the tour in advance and look for the weather forecast. The boat tour will take you through breathtaking scenerie with large cliffs, waterfalls and wildlife.
After the tour you can drive further up north through quaint fishing villages . Once back in Norris Point, just look around and you will find on every corner something to see.
On day two, head to the Tablelands, a one hour drive around the Bay.Then you will finally reach the Tablelands, one of the few places in the world where you can see the dismantled earth crust and you will have the feeling to walk on the moon. Take your time and do the hike which will lead you closer to the mountains.
Afterwards drive further to the ocean and enjoy a dinner and a wonderful fisherman scenerie.
On day 3, take it easy and book a boattour which leads you through the bay near Norris Point, you might see dolfins, eagles and other wildlife