>>6047461
It's a lot less straightforward than say, a SNES or Gameboy emulator, where you can just drop the .rom file on the program and bam, there's your videogame.
DosBox can run most Dos games, often fine, some of the original non-Dos .exes actually still work fine even. Some games have source ports, if they're particularly popular they may have many, or a dedicated VM program, like ScummVM.
Straight up virtual machines can work, but some games can just be fidgety bitches anyway and not want to work properly, which might be original behavior (so points for authenticity). There's also various compatibility patches, some which are even official, from the very few devs who still support their real old games.