hi guys. I want to create some thing like this image. but i dont know which kind of light acts like this.
There is no light that produce this effect out of the box. But you may want to give the bloom pass a try like demonstrated in these examples:
https://threejs.org/examples/webgl_postprocessing_unreal_bloom
https://threejs.org/examples/webgl_postprocessing_unreal_bloom_selective