Dwarf Fortress
From PCGamingWiki, the wiki about fixing PC games
Dwarf Fortress is an ASCII freeware game by Bay 12 Games with elements of city building and roguelikes known for its steep learning curve. It is available for Windows, Linux, and Mac.
Tutorials
The Complete and Utter Newby Tutorial captnduck YouTube tutorial series
Mods
The Lazy Newb Pack Is recommended for beginners as it adds textures to the game and makes it more accessible.