A game like this isn’t going to be without combat, which you will do plenty of during the main story and even outside of the story. Before delving into the specifics of combat, you will need to learn that while most of your fighting will be against human enemies, there will also be animals you will be fighting against.
You will be introduced to the Detection Meter in the opening of the game. Whenever a human enemy sees you, a white arrow will appear above their heads and start to fill in. If you hide before it fills up, then it will go down and enemies won’t come after you. However, should the meter fill up completely, it will flash and then the enemy will attack.