Check out example codes for "how to make a top down movement in unity 2020". It will help you in understanding the concepts better.

Code Example 1

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

public class PlayerMovement : MonoBehaviour
{
    public float moveSpeed = 5f;

    public Rigidbody2D rb;
    public Camera cam;

    Vector2 movement;
    Vector2 mousePos;

    // Update is called once per frame
    void Update()
    {
        movement.x = Input.GetAxisRaw("Horizontal");
        movement.y = Input.GetAxisRaw("Vertical");


        mousePos = cam.ScreenToWorldPoint(Input.mousePosition);
    }

    private void FixedUpdate()
    {
        rb.MovePosition(rb.position + movement * moveSpeed * Time.fixedDeltaTime);

        Vector2 lookDir = mousePos - rb.position;
        float angle = Mathf.Atan2(lookDir.y, lookDir.x) * Mathf.Rad2Deg - 90f;
        rb.rotation = angle;
    }
}

Code Example 2

Rigidbody2D body;

float horizontal;
float vertical;
float moveLimiter = 0.7f;

public float runSpeed = 20.0f;

void Start ()
{
   body = GetComponent<Rigidbody2D>();
}

void Update()
{
   // Gives a value between -1 and 1
   horizontal = Input.GetAxisRaw("Horizontal"); // -1 is left
   vertical = Input.GetAxisRaw("Vertical"); // -1 is down
}

void FixedUpdate()
{
   if (horizontal != 0 && vertical != 0) // Check for diagonal movement
   {
      // limit movement speed diagonally, so you move at 70% speed
      horizontal *= moveLimiter;
      vertical *= moveLimiter;
   } 

   body.velocity = new Vector2(horizontal * runSpeed, vertical * runSpeed);
}

Learn ReactJs, React Native from akashmittal.com