The bundle with both games are on sale on PSN right now, and I would recommend that, as both games are great. Red Dead Redemption 2 is actually a prequel to Red Dead Redemption, so I would recommend playing RDR2 first. The extended epilogue is especially important for setting up the events of RDR1. You could just play RDR2 and get a complete story for that game, since it's chronologically first. But for the complete story, play both.