Collision detection of certain ojects

I could not find any info for detecting collision between two (or more) certain objects. For instance;

detect if x collides y then destroy y

how is it possible to write such code,I could not find any info for detecting collision between two (or more) certain objects. For instance;

detect if x collides y
then destroy y

how is it possible to write such code

edit------------------

i figured out some things about it, but now the question is how can i detect collision of instantiated prefab?

prefabs are instantiated with the name prefab(copy), so using

if(collision.gameobject.name == “prefab(copy)”) should detect it.