2d Top Down Shooter Jerky Movement

Hey guys I am a newbie in unity. Currently I am making a 2d top down shooter based game. And here comes the bug. So character movements I am using Brackeys top down shooting tutorial. And here is the code.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerMovement :MonoBehaviour


[SerializeField]private float movementSpeed = 5f;
[SerializeField]private Camera cam;
private Rigidbody2D playerRb;
private Vector2 movmentVector;
private Vector2 mosusePos;
private Vector2 lookDirectionVec;

 //Start Called once
 private void Start()
     playerRb = gameObject.GetComponent<RigidBody2D>();


 //Update Called Every Frame
    private void Update()

 //Fixed Update 
 private void FixedUpdate()
         + movmentVector * Time.fixedDeltaTime);
     // playerRb.velocity = new Vector2(movmentVector.x, movmentVector.y);

 private void GetingInput()
     Vector2 inputVector = new Vector2(Input.GetAxisRaw("Horizontal"),Input.GetAxisRaw("Vertical"));
     movmentVector = inputVector.normalized *movementSpeed;

     lookDirectionVec = cam.ScreenToWorldPoint(Input.mousePosition) - transform.position;
 private void MouseRotation()
     float angleToRotate  = Mathf.Atan2(lookDirectionVec.y,lookDirectionVec.x) * Mathf.Rad2Deg - 90f;
     Quaternion qRotation = Quaternion.AngleAxis(angleToRotate,Vector3.forward);
     transform.rotation = qRotation;


But whenever I test the game the movements are jittering. Like the shutter the movement. I found some solutions on web articles and unity forms. The first I tried is to change RigidBody2d.MovePositions() to RigidBody2d.Velocity but the result is also the same and the second one is to change the camera size 5 to 10. Second one is kind of a work but it stills jittering. So any solutions to this. Here are the camera properties

hey. try and change the rigidbody from interpolate to one of the other options. i cant tell if this is a permanent solution but that worked for me.,hey, i think i have found a solution. try and change your rigidbody from interpolate to either extrapolate or none. i don’t know if this is a necessarily good solution since im pretty new to game dev aswell, however that is what worked for me.