please explain me aboutrelationbetween intensity energy and frequency of em waves

There is none. Intensity is the brains interpretation of the amplitude of a wave. (The height). Frequency is the amount of waves which pass a particular place in a specific time period. To use sea waves as an example, you could have 5 or 6 waves breaking on the shore, per minute. Then you get big and small waves. So intensity is the size of the wave and frequency is, well, how frequent the waves are. They are unrelated except that both factors are properties of waves.