Install a macos gaming emulator
Get started with Unity
Emulators are available for a number of classic platforms and Openemu attempts to cover them all. With the addition of some game ROMS you will be able to play retro classics that somehow feel harder to play than their modern counterparts. Be sure to only ever use ROMS that you already own – it is not legal to simply download games and you run the risk of obtaining files that can damage your Mac.