is it possible to use i2c as 2way communication between nodemcu & arduino.
Not really. I2C is a bus with a strict master/slave hierarchy. So the master is asking the slave for data and the slave responds to this request but the slave is not able to send something to the master without the read request from the master.
i used Wire.requestFrom(,); , but it is not getting data.
im not getting any proper examples.
How did you connect it? The UNO runs on 5V, the ESP on 3.3V. A direct connection may damage the ESP.