Cannot implicitly convert type 'UnityEngine.Rigidbody2D' to 'UnityEngine.Rigidbody' error in Unity 2D core

I am new to Unity and I am following a tutorial, but when I write the code I get this error:

Cannot implicitly convert type ‘UnityEngine.Rigidbody2D’ to ‘UnityEngine.Rigidbody’

The code:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerCtrl : MonoBehaviour
{
    public float movSpeed;
    float speedX, speedY;
    Rigidbody rb;

    // Start is called before the first frame update
    void Start()
    {
        rb = GetComponent<Rigidbody2D>();
    }

    // Update is called once per frame
    void Update()
    {
        speedX = Input.GetAxisRaw("Horizontal") * movSpeed;
        speedY = Input.GetAxisRaw("Vertical") * movSpeed;
        rb.velocity = new Vector2(speedX, speedY);
    }
}

How can I fix this?
I tried debugging and rewriting the code and the issue persists.

>Solution :

Your rb variable in the PlayerCtrl class has the type for a 3D rigidbody:

Rigidbody rb;

Change it to Rigidbody2D instead:

Rigidbody2D rb;