How is transmit power of zb pro module 63 mW when it is transmitting 295 mA @ 3.3 V

I think there is some confusion. The current draw has very little to do with the amount of RF power out that you can produce. Simply put, there is no direct coordination between the two. This specific module with the components used requires it to use up to 300mA of current to transmit a signal at 63mW.