Correct use of transform.position of UI element into game screen

Hello! I am trying to get my UI to transform into the position of my mouse cursor, when I click the mouse button. To give you an idea visually: I am making an action box for an adventure game in 2D Unity. So, whenever you rightclick (Mouse1) there will pop up an action menu at the right-clicked position in the game.

I have tried playing around with WorldToScreenPoint, but I get confused on how I really get this to work. Here is some of my code:

 public class FrankMove : MonoBehaviour {
 
     bool isMoving;
 
     public bool showActionMenu;
     GameObject actionMenu;
     GameObject actionMenuBox;
 
     private float Xdif;
     private float Ydif;
 
     public float speed;
 
     private Vector2 positionHit;
     private Vector2 positionDirection;
 
     void Start() {
         isMoving = false;
         showActionMenu = false;
         actionMenu = GameObject.Find("ActionMenu");
         actionMenuBox = GameObject.Find ("ActionMenuBox");
         actionMenu.SetActive(false);
         actionMenuBox.SetActive(false);
     }
 
     void Update () {
         Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
         RaycastHit2D hit = Physics2D.Raycast(ray.origin, ray.direction);
 
         //Movement
         if(isMoving == true && showActionMenu == false) {
             rigidbody2D.velocity = positionDirection.normalized;
 
             if((positionDirection.x < 0.02f && positionDirection.x > -0.02f) &&
                (positionDirection.y < 0.02f && positionDirection.y > -0.02f)) {
                 isMoving = false;
             }
         }
 
         Xdif = positionHit.x - transform.position.x;
         Ydif = positionHit.y - transform.position.y+0.3f;
         positionDirection = new Vector2 (Xdif,Ydif);
 
         if(Physics2D.Raycast(ray.origin,ray.direction)) {
         if(Input.GetKeyDown(KeyCode.Mouse0)) {
                 positionHit = hit.point;
                 isMoving = true;    
             }
         }
 
         //ActionMenu scripting
         if(showActionMenu == true) {
             actionMenu.SetActive(true);
             actionMenuBox.SetActive(true);
         }else if(showActionMenu == false) {
             actionMenu.SetActive(false);
 
         }
 /*********************HELP IS NEEDED HERE*******************/
         if(Input.GetKeyDown(KeyCode.Mouse1)) {
             showActionMenu = true; 
             //When ActionManu is true, I SetActive my UI gameobject.
             //ActionMenu positioning over mouse should be here
         }
     }
 }