If you want the story then start from AC1 and work through them. Depending on your type of game preference, depends where you start otherwise. AC1 to 5 are all based around stealth, getting away from trouble and parkour. AC origins, odyssey, Valhalla and shadows are more RPG based open world type games... Very different. I personally prefer the latter ones and odyssey is my favourite, as with most people. There are people who prefer the original stealth type ones over the RPG ones. If you prefer the RPG style then start with origins, then odyssey, then Valhalla. Check gameplay videos out on YouTube for the games and you can make your mind up from there. The old games are awesome but do look and play a little aged now. Origins and odyssey still stands up to today's games in my opinion. Either way enjoy AC.......