ça y est vs. c'est fait

Bonjour Johnny ! Actually, French people would often say "Ça y est, c'est fait !" together like this! While "c'est fait" literally means "it's done" in a matter of fact way, "ça y est" is more of an expression of relief or satisfaction at the realisation or completion of an action. You will use "ça y est" when you finally got somewhere, or when someone finally manages to fix something.... The key word here is "finally". In a similar way to "Ça y est", you can also use the versatile "Voilà". I hope that's helpful! À bientôt !