First option needs to be to ask the user if it is a recentagle or a circle.
Next get user to input the dimensions of the pool. Lets say it is a rectangle and they enter 25, 5 and 6.
You will creates variables to store these. e.g. int length, int width, int height.
You will now do a calculation of length * width * height and the result of this will be store in a new variable int volume.
You will then do a simple output message saying "Hello user the volume of your pool is 'volume';
In psedo code
Output "Hello user what is your name?"
INPUT "user please input name" <-- assign to int userName
Output "Please indicate if your pool is a circular pool or a rectanglur pool."
input : press 1 for circluar or 2 for rectangular.
So user then inputs all the measurements.
then you do
length * height * width = volume
you get the idea...
The hardest part of this assignment is the formula but I've already shown you how to calculate the area of a cube.
to caulate the area of a circular pool is is pi x r2 pi is 3.14 and r is radius of the pool.
so if the pool is circular you would create a variable called int pi and then you would just get the user to input the radius.
Also they want a shallow end and a deep end so you may have to add these two toegther.
Hopefully this is of some help but if not sorry for wasting your time.