UNIX script coding help?

Unix script coding help?
i am trying to write a code that will display following menu to user:
(A) Add
(B) Subtract
(C) Multiply
(D) Divide
(E) Modulus
(F) Exponentiation
(G) Exit
Then ask user for choice (A-F). After taking users choice ask user for two numbers and
perform chosen operation on those two numbers. The program should keep asking
for choice / numbers unless user chooses �G' for exit.

What have you tried so far? Is this a homework question? If yes, there is a separate section for that.

what section is it can you link it for me
thank

There is a section called "Homework" in home page. And no I cant link it for you, it needs additional information regarding the question.