The first true PC game was Spacewar (1962); it's that game where two ships fly around a celestial body shooting at each other while trying to avoid getting sucked in by gravity. It was also the first famous game, the first influential game, the first game to be expanded or patched (the most well-known example being its true to life moving starfield background named "expensive planetarium," although the game's gravity and hyperspace mechanics and simulated angular momentum and space weather were not in the initial game either), the first game with options (any of those features could be turned off at the player's leisure), the first arcade game, the first game to be ported (to the arcade), the first game with a story, and also the first game based on a literary source (the Lensman series of science fiction novels by E. E. Smith). The first adventure game was Colossal Cave, which came out 14 years later. I'm not really a big fan of adventure games, but the only one of those games I can think of that doesn't fall prey to that genre's "mentally ill hobo" gameplay trappings is Mode (1996), which worked somewhat like the hypothetical game you described (looking for stuff is mostly pointless since the game is primarily driven by who you talk to and how well the conversations go, progress is less about creating new options and more about becoming better informed about which options to take, the game is about a mystery which you probably won't even notice if you don't know what to look for, and there's a very fixed time limit which draws closer with every choice you make).