trajectory arc not working, how to build a trajectory arc for aiming

I want to build a trajectory arc when I am dragging my mouse ie I want an aiming system and my code isn't working.

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class movement: MonoBehaviour
 {
     public float velocity;
     float time;
     float x;
     float y;
     float tt;
     float g;
     Vector2 force;
     public float power = 2.0f;
     Vector3 startpoint;
     Vector3 endpoint;
     Camera cam;
     public Vector2 maxpower;
     public Vector2 minpower;
     public Rigidbody2D rb;
     Vector3 currentposition;
     Vector3 sp;
     LineRenderer lr;
     int resolution = 10;
     Vector3 newpoint;
     // Start is called before the first frame update
     void Start()
     {
         time = 0f;
         g = Mathf.Abs(Physics2D.gravity.y);
         cam = Camera.main;
         lr = GetComponent<LineRenderer>();
     }
 
     // Update is called once per frame
     void Update()
     {
         time += Time.deltaTime;
         x = gameObject.transform.position.x + velocity * time;
         tt = time * time;
         y = gameObject.transform.position.y + (g * tt) / 2f;
         if(Input.GetMouseButtonDown(0))
         {
             startpoint = cam.ScreenToWorldPoint(Input.mousePosition);
             startpoint.z = 5;
         }
         if(Input.GetMouseButton(0))
         {
             sp = new Vector3(gameObject.transform.position.x, gameObject.transform.position.y, 5);
             currentposition = cam.ScreenToWorldPoint(Input.mousePosition);
             currentposition.z = 5;
             LineRenderer(sp);
         }
         if (Input.GetMouseButtonUp(0))
         {
             endpoint = cam.ScreenToWorldPoint(Input.mousePosition);
             endpoint.z = 5;
             force = new Vector2(Mathf.Clamp(startpoint.x - endpoint.x, minpower.x, maxpower.x), Mathf.Clamp(startpoint.y - endpoint.y, minpower.y, maxpower.y));
             rb.AddForce(force * power, ForceMode2D.Impulse);
             x = x + velocity * time;
             y = y + (g * tt) / 2f;
             EndLine();
         }
     }
     public void LineRenderer(Vector3 p)
     {
         lr.positionCount = resolution;
         Vector3 arc = p;
         for(int i=0;i<resolution;i++)
         {
             newpoint = calculate(arc, i / (float)resolution);
             lr.SetPosition(i, newpoint);
             arc = newpoint;
         }
     }
     public Vector3 calculate(Vector3 point, float t)
     {
         point.x += velocity * t;
         point.y += 0.5f * g * t * t;
         return point;
     }
     public void EndLine()
     {
         lr.positionCount = 0;
     }
 }
 
 

This is the code, the drag and move are working but the arc is not executing. Please help.