Movement.cs

using UnityEngine;

public class Movement : MonoBehaviour
{
    private Rigidbody rigidbody;

    [SerializeField]
    private float speed;

    [SerializeField]
    private ForceMode forceMode;

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

    // Update is called once per frame
    void Update()
    {
        // EXAMPLE 1
        float h = Input.GetAxis("Horizontal");
        float v = Input.GetAxis("Vertical");
        Vector3 velocity = new Vector3(0, 0, v);
        velocity *= speed;
        velocity -= rigidbody.velocity;

        rigidbody.AddForce(velocity, forceMode);
        
        /* EXAMPLE 2
        float h = Input.GetAxis("Horizontal");
        float v = Input.GetAxis("Vertical");
        Vector3 velocity = new Vector3(0, 0, v);
        velocity = transform.TransformDirection(velocity);
        velocity *= speed;
        velocity -= rigidbody.velocity;

        rigidbody.AddForce(velocity, forceMode);
        transform.Rotate(new Vector3(0, h, 0));
        */
    }
}