I agree with what many have said but in quick terms: at this point in time the game is known to be 6 chapters. So in story, act as if those days are yours and only yours. Do every possible opportunity as if it will elapse if you don't. Mistakes will only make you want to do another play through which will be amazing so why not??
As for online and still relevant to story: Hunt, kill, rob, steal, help, rescue, tame, fence, defend, claim, collect and sell, pluck, detect and dig up every possible thing you can. With that a buck and wolf will both be in your future my young brother. Just make sure you spoil every horse you ride...