Did you get the radios to work by themselves before adding all of the other code. Robin2's simple rf24 tutorial has some good example code to test the radios with and a program that you can use to verify the wired connections between the radios and their processors.
That statement conveys no real information that we can use to help you.
That will not work.
Use itoa() to convert an int to a string.
Or use dtostrf() to convert a float to a string.