Hey! Welcome and hopefully you'll enjoy it here.
I'm still rather new myself, but I'm happy to share what little I have figured out for myself so far.
Personally I find that doing arena (and currently the Icerun one) is a good source of income once you figure out how it works. Basically you combine 3 of the same 1 star creature to make it 2 star and then the same process to get to 3 star. And you gotta check the different synergy aspects to build a good team.
Some companions give you a small amount of pebbles for playing with them too. And the different activities listed (kinda like daily quests) give you a small amount sometimes too. You can see what you get from each activity quest by hovering over it.
As for feeding your wolves, that's only needed when you don't wanna wait for their stamina to be restored. Through Fishing you can get raw fish (which gives roughly 5 stamina) and you can cook it. Cooked food gives a bit more stamina. Activities like Mining, Hunting, Fishing take a certain amount of stamina and so does exploring in the campaign.
On the page of each wolf you have a Feed button from where you can pick specific food items from your inventory. There are also Feed All buttons of sorts during the campaign and such, but I prefer to go through them one by one because the button to feed them all takes whatever it wants rather than letting you choose.
Oh...and check the Mole Market every few hours because it refreshes and has other stuff + one free random item.
Hope it all makes sense somehow.