There is always a confusion between Fate/Zero light novel series and the Fate/stay night light novel series. Although Fate/stay night was released first as an anime, the setting of Fate/Zero is 10 years ahead of the setting of Fate/stay night. Chronologically it should be Fate/Zero first then Fate/stay night but if we are talking about the order of its release then Fate/stay night should go first before Fate/Zero.
Since Fate/Zero has two seasons and it is pretty much on the edge of Fate/stay night then there shouldn’t be a third season for this anime series. I am not so sure though since I am not an insider and I don’t have that much connection on anime licensing companies and networks that reproduced the anime.
If you know that exact order or the proper finish of this anime series, please let me know. Thanks.