There's a major emphasis on puzzle solving as a means of connecting communities in "Death Stranding" — Sam is exploring the "United Cities of America" (UCA), attempting to re-connect them in the wake of disaster.
Additionally, exploration is another core component of the game, while carefully avoiding the "beached things" (BTs) that roam the American landscape (we'll get to those in a moment).
There's also an asymmetric co-operative element to the game: "Send supplies, share safe houses, and walk in the footsteps of fellow couriers to reunite civilization," the game's description says.
Moreover, the concept of dying in "Death Stranding" is a little different than most games. "Lose your life during combat and you'll find yourself in an upside-down realm, searching for a way back to the living," it says. Moreover, any actions you take in that upside-down realm could have an impact later on in the game.