I have a doubt on whether I can use just esp8266 wifi module in place of nodemcu module for receiving data from nrf24l01 module and uploading the data to the web server. If it is possible then what is the difference of using nodemcu and esp8266 module for the same purpose.

 

See if you can get the code to compile ok. I would imagine it would work.

 

NodeMCU - Wikipedia

NodeMCU is an open source IoT platform. It includes firmware which runs on the ESP8266Wi-FiSoC from Espressif Systems, and hardware which is based on the ESP-12 module. The term "NodeMCU" by default refers to the firmware rather than the development kits. The firmware uses the Lua scripting language. It is based on the eLua project, and built on the Espressif Non-OS SDK for ESP8266.
You can program an ESP8266 as a NodeMCU using Lua language or with the Arduino GUI like an Arduino.
You can also program it with "AT" commands.
Get Started With ESP8266 Using "AT Commands" Via Arduino: 5 Steps
https://www.instructables.com › technology › wireless