I need a banking system in C#!

How to make C# codes to disable buttons UPDATE,DELETE,EXIT when clicking to ADD button which is enabled?

I have for buttons INSERT,UPDATE,CLEAR AND DELETE How can I make codes in C# such that
when clicking to one of them when executing others are shown to be Disabled buttons?

Could you please show me how to generate prime numbers in C#?

For the buttons you may wish to use a combination of if statements and button.enabled.

Show me your logic for prime numbers

Prime numbers have been done so many times before, that if you do a search on this site, you will find what you need.

Try Enabled property. Post your code here if any.