how to get component of this gameobject unity code example

Example 1: how to get component in unity c#

GetComponent<Rigidbody>(); //used to find component on character (rigid body can be changed)
GameObject.FindGameObjectWithTag("player"); //finds any game object in the scene with this tag

Example 2: unity create gameobject with component

GameObject go = new GameObject("Test", typeof(MeshRenderer), typeof(MeshFilter), typeof(YourScript));