Character Contoller

PlayerMovement.cs

using UnityEngine;

public class PlayerMovement : MonoBehaviour
{
    [SerializeField] private float speed = 10f;
    [SerializeField] private float jumpHeight = 10f;
    [SerializeField] private float gravity = -9.81f;
    [SerializeField] private float groundDistance = 0.4f;
    [SerializeField] private float runSpeed = 20f;
    [SerializeField] private Transform groundCheck;
    [SerializeField] private LayerMask groundLayer;

    private Vector3 _velocity;
    private CharacterController _controller;
    private bool _isGrounded;

    private void Start()
    {
        _controller = GetComponent<CharacterController>();
    }

    private void Update()
    {
        _isGrounded = Physics.CheckSphere(groundCheck.position, groundDistance, groundLayer);

        if (_isGrounded && _velocity.y < 0)
        {
            _velocity.y = -2f;
        }
        
        var x = Input.GetAxis("Horizontal");
        var z = Input.GetAxis("Vertical");

        var transform1 = transform;
        var move = (transform1.right * x) + (transform1.forward * z);

        var currentSpeed = Input.GetButton("Run") ? runSpeed : speed;
        
        _controller.Move(move * (currentSpeed * Time.deltaTime));

        if (Input.GetButtonDown("Jump") && _isGrounded)
        {
            _velocity.y = Mathf.Sqrt(jumpHeight * -2 * gravity);
        }
        
        _velocity.y += gravity * Time.deltaTime;

        _controller.Move(_velocity * Time.deltaTime);
    }
}