The interact action (F) is the hot key you’ll be using most.
The [F] icon will display when you’re near a valid interact target.
You can use interact to accept quests, complete quests, and open vendor screens.
It also lets you loot defeated creatures and manipulate certain objects.
Just don’t get too used to hitting F repeatedly, or you might miss something important.
* The guide may differ from the actual game play due to updates and content changes.