I like to play a game for months. I get addicted to a single game, drop all other games and focus all my attention on it until I can't stand it anymore. With a good game, you won't easily get bored.
I'm usually partial to a sandbox single player game, like Red Dead Redemption 2 or Skyrim. However, a multiplayer game to play with friends, like Team Fortress 2, where you work toward a common goal, can be really great.
Bored? Generate a random list of games pick one to try. Games are new and old, from any platforms (mobile, consoles, PC, etc.), in any style (shooting games, funny games, MMO, etc.), and any cost (paid/free).