I am a new in blender and I have made this mobile device that have blue texture. And logo above it.But i cannot figure out that how to add light glow (emission) on logo.. Please guyz help me, this is my first project that i am working on it..
Just plug image node ("Logo") color socket into Emission socket of Principled BSDF node. I added node Convertor > Math type Multiply to increase strenght of light.
If your logo image is not black&white use ColorRamp node, RGB Curve node or what ever that make it BW.
Works for Cycles Render engine. Eevee does not support mesh lights. But you can try distribute the light of emission texture by adding Irradiance Volume object. See How to make mesh lights work in Blender Eevee?