Hey there, and welcome to Lorwolf!
As Fox174 said, I'd do all the quests in every pack's Campaign. It unlocks every zone so you can go back to your favorite areas and grind when you need resources like food or want to try and find Wild Wolves to add to your pack.
Always cook, fish, and farm. Cooking is a great way to make sure the stuff you get through fishing and campaign gives you more stamina points per food item. Farming is also a great way to stockpile foods. Stamina was one of my main buzzkills when I first joined and I would complain to all my friends about it, but being a new player it's hard in the food department at first. But now, it's easy to just grind for hours on end with all the food I have stored away.
Speaking of food, there is an Auto Feed option located in your den under the Den Statistics box. You can prioritize your food that your wolves consume there. For example, I keep things like Cooked Meat and Fish on auto feed for when I grind in Campaign, while stuff I grow through Farming is stuff I hoard for feeding my wolves later for things like mining, fishing, and Gauntlet.
Use Companions to your advantage. There are companions that are cheap, like the Basidio, that when equipped to your wolf and interacted with will yield you XP. They basically will help level your wolves without grinding in Campaign! There are other companions that yield things like food, trinkets, and even pebbles!
That's all I can think of for now. Hope it helps you out a bit. And as always, just have fun! :D
