How to do this Effect on GameObject like Border light?

Agreed, your image is far too small to see exactly the effect you're looking for. I'm assuming, from what I can make out, you're looking for a sort of toon-ish glow. Have you tried tweaking Unity's built in toon shaders with different outline colors and intensities? Also, for the second part you can simply use an attached script with OnMouseEnter() and OnMouseExit() to change the material via Renderer.material like this:

 public Material glowingMaterial;
 public Material normalMaterial;
 
 function OnMouseEnter() {
     Renderer.material = glowingMaterial;
 }
 
 function OnMouseExit() {
     Renderer.material = normalMaterial;
 }

Then, just drag the desired materials into the inspector window.