@Peter Withe Welcome aboard! FIFA 14 has a limited amount of patches, but it does have the granddaddy of them all: the
Classic Patch. The Classic Patch is an encyclopedia of football history and features teams from all eras. Depending on what era you like best (mine are 90s Champions Leagues and old World Cups), you can play with whichever team your heart desires and get lost in football history.
For modern leagues, the
FIFA Infinity Patch last updated in April 2022.
ModdingWay has a great one where you can switch the databases from the original FIFA 14 to updates through the 17/18 season. There's a specific 2014 World Cup mode that I'm playing that is excellent.
They are relatively easy to add, but will take some time overwriting files and then you will need to "regenerate" the game, which I can help you with if you don't know it. ModdingWay is an all-in-one installer that makes installing easier.
To have multiples, I suggest you download multiple versions of the original game and rename the folder based on which one you want to use. That way, you are starting with a clean game and there's less unneeded file overlap.