Savings account Class

I am new to the site and I am having trouble with my code. below is the question and the application I am trying to do.

Create Class savingsaccount. Use a shared class variable to store the annualInteresteRate for all SavingsAccount. Each object of the class contains a PrivateInstance variable savingsBalance indicating the amount the saver currently has on deposit. Provide the CalculateMonthlyIntereste method to calculate the monthly interest by multplying the savingBalance by the annualInteresteRate by 12; this inteest should be added to savingsBalance and retunred to the method caller. Provide a shared method ModifyingInteresteRate that sets the annualInteresteRate to a new value. Write an application to test class SavingsAccount. Instantiate two savingsAccount objects, saver1 and saver2, with balances of $2,000.00 and $3000.00, respectively. Set annualInterestRate to 4%, then calcule the monthly interest and display the amounts of interest earned and the new balances for each of the savers. Then set the annualinterestrate to 5% and calculate the next month's interest and display the amounts of interest earned and the new balances for each of the savers.

I have never done this and I am not sure where to begin. I was wondering if someone can point me in the right direction to get started.