How to add material to object in code unity code example

Example 1: how to set material c unity

Renderer rend = GetComponent<Renderer>();
 if (rend != null){
     rend.material = newMaterialRef;
 }

Example 2: how to change material in script unity

public Material Material1;
  //in the editor this is what you would set as the object you wan't to change
  public Renderer Object;
 
  void Start()
  {
       Object.material = Material1;
  }