-Portal 1
-Portal 2
-Ori and the blind forest
Portal 1&2 have fun puzzles to solve if you are into that stuff and the story is cool with nice sarcastic humor.
Ori and the blind forest is a metroidvania probably the coolest metroidvania with stunning visuals and nice music. The story is nice too if you are after stories.
All are strategic games that require you to solve puzzles to progress which i think makes games fun and brings interactivity to a level beyond other games regardless of graphics(Not saying graphics are bad but the games are worth playing).
All three games are under 10 GB and shouldn't take you more than a week to finish.

