Go up ahead. After a short cutscene, Lara will be attacked by a large bear. At the moment, fighting the animal makes no sense, but the game itself does not require you to. The only thing you can do is run. One misstep and the bear will get you.
Sprint ahead (push the left analog stick). Watch out not to run or jump into snowdrifts, because they slow you down enough for the bear to get you. Finally, run over the fallen tree trunk and take a long leap. Note that while you take a leap, you can make up for your path, which will allow you to avoid bad landing in the future.
Soon, you will reach a makeshift shelter of roots of the tree above, which will in a moment stop the bear's charge. When you are prompted by the game, start tapping Y button rhythmically for several seconds.
The last phase of the encounter with the bear is a simple QTE. At the moment, at which the bear is standing on its hind legs, takes a swipe, perform a dodge by pressing the B button. A moment afterwards, press the Y button - in this case, you will have to race against time for the first time, because you need to manage to do this before the diminishing circle reaches the center. If you manage to do this, you will watch another cutscene, where Lara drops to a lower level.