and if you're looking to get into the games, I highly recommend Sonic 1 Forever, Sonic 2 Absolute and Angel Island Revisited. they're all fan-made widescreen remasters with a bunch of bells and whistles that make the experience so much better, and unlike the...questionable compilation that is Sonic Origins, are completely free.
alternatively if you're just after the games themselves without all of that, you can easily download either Retroarch or Kega and just emulate them. either way you're gonna enjoy it!