So what is the chill mode game
Chill mode is playing the game for as long as you want. Most of your time will be spent talking to people & improving relationship by doing something for them. They could reveal something that benefit you in the future. That's core game loop of the game.
Of course you can just ignore talking to people but you'll make progresss lower. The game will become boring if you don't talk to people because you'll miss lots of interesting objectives.
Take note there's no enemies in the game so there's no worry if you go outside after midnight or fishing or foraging in the forest in darkness.