At present i am using 4*4 keypad with arduino mega,i need a keypad which contains menu ,backspace ,enter and some other options,may i know which keypad will be suitable for arduino mega.
How many total keys do you need? you can call a key anythng you want in software. On my 4x4 keypad I use * for decimal point and # for enter.
keypad which contains menu ,backspace ,enter and some other options
What is "other options"? I think there is no keypad meet your requirement with "other options".
Instead, You can use a normal 4x4 keypad, and then stick new label on the keys as you want.