If I wanted to set the stepper to display in red if coffee is 2 or more, can I add that to this line or does it have to be separate? I'm struggling.

I tried adding it to this below, but I can't get it to work!

Stepper(coffeeAmount == 1 ? "1 cup" : "(coffeeAmount) cups", value: $coffeeAmount, in: 1...20)

No, you can't do it directly on that line. You do it on a modiifier method for Stepper, using .foregroundColor

 .foregroundColor(coffeeAmount > 1 ? .red : .primary )

You would have also discovered that the Stepper was not displaying the correct amount of coffe cups.

Stepper(coffeeAmount == 1 ? "1 cup" : "(coffeeAmount) cups", value: $coffeeAmount, in: 1...20)

would display (coffeeAmount) cups when the number of coffee cups was 2 or more. Instead you need to use string interpolation.

Stepper(coffeeAmount == 1 ? "1 cup" : "\(coffeeAmount) cups", value: $coffeeAmount, in: 1...20)

So the code would be

Stepper(coffeeAmount == 1 ? "1 cup" : "\(coffeeAmount) cups", value: $coffeeAmount, in: 1...20)
    .foregroundColor(coffeeAmount > 1 ? .red : .primary )