There are all sorts of ways to approach this kind of scenario, but something to consider is that, for someone who has never played a game, they're going to be completely unfamiliar about all the intricacies of systems and mechanics. To an experienced player, these elements may come natural, but I guarantee they didn't always and do take time to understand and become comfortable with.
My selection focuses on 2D games or 3D games which aren't heavily action-focused, because navigating 3D spaces and camera control are mechanics which are difficult to learn and operate. I took time to consider the various gameplay components certain genres are known to have which can serve as a stepping stone for newcomers to seek out more complicated games and genres. Also, nearly all of my choices reflect games I've personally played or are from a series I've played, and ones that I feel go beyond listing gaming classics like Pong or Tetris which are almost always present on these sorts of lists. I would also consider my choices to be suitable for all ages.
Among Us: While its gameplay is simple to understand, it requires the player to prioritize certain actions over others while also needing to use deductive reasoning in a social scenario. Because players are assigned to either a defensive or offensive role, how one plays will vary dramatically, and there are various tactics involved to employ while on the offensive, whereas an eye for detail must be learned while on the defensive. Because of the game's matchmaking setup, no team matches will play the same.
Bit.Trip Presents... Runner2: Future Legend of Rhythm Alien: Known for its more arcade-like gameplay, Runner2 helps players train their reaction speeds against various course obstacles, all while actions are set to a rhythm to follow. The game's generous checkpoint system is also a highlight, as it grants an easier means for players to overcome challenges.
Flower: Apart from its art game aesthetic, Flower is an ideal example at introducing players to 3D environments. It offers players an abstract narrative that's simple to understand yet one that's still a marvel to experience. Its entire presentation leaves an impactful impression, and I think it introduces the idea that games can be much more than just a tool for amusement effectively.
Minecraft: Introducing a sandbox type game seems important, and Minecraft seems to best suit that criteria. Players can choose what sort of play experience they'd like to have at any given time, that being Survival or Creative Modes. Of course, that the game is procedurally generated means that it will never be possible to fully explore its world, even should players want to. At the same time, a vast array of mod and customization options are also available to try. Due to its simple art style and world design, navigating its 3D environments doesn't seem that it'd be difficult to grow used to. Should players want to experience Survival Mode, straightforward combat and survival mechanics without convoluted systems, or ones which mimic real world needs such as health and hunger, are present.
Ms. Pac-Man: Because of its single-screen gameplay, Ms. Pac-Man is an ideal choice for players to practice careful precision and reactive decisions. Enemy encounters are semi-randomized which means there are no set patterns to follow, so players won't be able to memorize enemy movements to overcome stages. Life system mechanics are introduced, and the corner power pellets offer a risk-reward system while managing time.
Pokémon Sword/Shield: While perhaps simple at first glance, Pokémon's battle systems do provide a notable level of difficult in learning, but these entries further modernize the franchise in helping overcome this problem, as type weaknesses and strengths are now present during battle. Its role-playing level mechanics are straightforward, and its stat system can be entirely overlooked by the casual player. However, should players want to invest in it, the system is always available. The game's local and online battle systems also offer a more intricate experience while trying to win.
Pushmo: I considered several different puzzle games as options, but I ultimately decided on Pushmo. There are no set timers, so players are free to carefully plan out their actions while adjusting for inevitable mistakes that will be made. At the same time, players move about a 2D plane but are required to solve 3D puzzles.
The Stanley Parable: Many praise certain types of open-ended games with player decisions having critical narrative consequences, yet The Stanley Parable is the only one which comes to mind that isn't bogged down with intensive combat or strategy systems. It's a game that regularly breaks the fourth wall while subverting all sorts of tropes, so its unsuspecting narrative offers a unique and memorable experience.
Super Mario Bros. Wonder: I've played few traditional Maio platformers, but I'm aware of Nintendo's distinguished efforts across the series which accommodates for new players and veterans alike. Altogether, they're excellent games for someone wanting to learn new gameplay mechanics to then later master everything each course offers. So, this means becoming acquainted with more basic elements like 2D navigation while under a time limit to more complicated ones like time-focused player inputs to maneuver through dangerous obstacles to collect optional items. Wonder is no exception, and it's most approachable and accessible than previous entries.
We Love Katamari: Apart from being a personal favorite of mine, We Love Katamari seems ideal for it being a low-risk type of game. It effectively introduces 3D camera control, time limits, the need to overcome spatial obstacles, and it's a fine example of a game which rewards player exploration. Additionally, its simple objective-based stages are straightforward to understand, and a fair number of stages with alternative types of objectives also exist which make the game even more varied to maintain interest.
