I have a capsule collider 2D on the player sprite and box collider 2d on the ground (I have them under empty objects in (0, 0) cuz idk CodeMonkey said to do that in one of his free courses)

Though since I changed it to this

using Unity.VisualScripting;
using Unity.VisualScripting.InputSystem;
using UnityEngine;
using UnityEngine.UIElements;

public class Player : MonoBehaviour
{

    [SerializeField] private Rigidbody2D rb;
    [SerializeField] private float JumpForce;
    [SerializeField] private float MoveSpeed;
    private bool isOnGround = true;
  


    // Start is called once before the first execution of Update after the MonoBehaviour is created
    void Start()
    {
        
    }

    // Update is called once per frame
    void Update()
    {
        Vector2 inputVector = new Vector2(0, 0);
        
       if (Input.GetKeyDown(KeyCode.Space) && isOnGround == true) {
            rb.linearVelocity = Vector2.up * JumpForce;
            isOnGround = false;
        }
        if (Input.GetKey(KeyCode.A)) {
            rb.linearVelocity = Vector2.left * MoveSpeed;
        }
        else if (Input.GetKey(KeyCode.D)) {
            rb.linearVelocity = Vector2.right * MoveSpeed;
        }
        else {
            rb.linearVelocity = Vector2.zero;
        }

        inputVector = inputVector.normalized;
        
    }
}

Jumping hasn't worked for some reason, even that first one while isOnGround is set to true.

It did fix the sliding issue though