Check out our answer to this Q here: https://www.nutriliving.com/answers/16299-Are-recipes-single-servings
Each recipe is for one 24oz cup unless otherwise noted. However, it is up to you on if you want to drink it all at once or share it.
For a meal replacement, then I'd suggest the entire recipe and choose one that contains some protein and healthy fats to make it more of a complete meal.
This will also depend on your hunger as well as your daily caloric needs.