How to change position of gameobject

Simple!!!

 // You'll need to set this either within the script or within the inspector.
 GameObject gameObjectToMove;

 public void MoveGameObject()
 {
     gameObjectToMove.transform.position = new Vector3(x, y, z);
 }

Using "transform.position" by itself is short for saying "this.transform.position", in which case you're simply referring to the game-object that the script is attached to.

when i try doing this it just moves it to a different position to what i put in heres my code

if (Input.GetKeyDown(KeyCode.Space)) { FishAnim.GetComponent().Play("PunkFishInvincible"); Speed += InvincibleSpeed; FishAnim.GetComponent().offset = new Vector2(7, -0.6f);

         FishName.transform.position = new Vector2(300, -150);

     }
     else if (Input.GetKeyUp(KeyCode.Space))
     {
         FishAnim.GetComponent<Animator>().Play("PunkFishIdle");
         Speed = 5;
        FishAnim.GetComponent<BoxCollider2D>().offset = new Vector2(0f, -0.6f);

         FishName.transform.position = new Vector2(0,-150);