I used esp8266 but I failed. Which wifi module i need to use. Would it matter if two modules use the same pins? Do 1 arduino install two different modules?
You need to post your program so we can see exactly what you tried. Equally importantly in this case you need to post a diagram showing how everything is connected. A photo of a pencil drawing will be good.
Your image says nothing about the other nRF24? Post that program also.
Have you successfully communicated between two nRF24s without the WiFi stuff? if not, that must be the first step.
Am I correct to assume that you can successfully communicate with the server using WiFi?