No Mac version was ever produced for these. Back in the days of Connectix Virtual Game Station, you could use that to run PSX games, and FFVII ran quite well (I played all the way through it; there was one glitch in menus but hitting SELECT made this a nonissue). I never played FFVIII on it, but I hear that it was supposed to work.
The problem is, you can't get VGS anymore, and even if you couldf it only runs if you actually boot into OS9; Classic won't work. This, in turn, requires a relatively old machine, and if you're new then you probably don't have one. I don't know about other PlayStation emulators on the Mac (though at least one exists), but you may have luck there.
I do not recommend trying to play FFVII or FFVIII through an actual PC emulator, such as Virtual PC. I've tried it myself, and although the games do run they're so slow as to be basically unplayable.