how to make first person camera in unity 3d code example

Example 1: fps camera unity

public float turnSpeed = 4.0f;
public float moveSpeed = 2.0f;
 
public float minTurnAngle = -90.0f;
public float maxTurnAngle = 90.0f;
private float rotX;
 
void Update ()
{
    MouseAiming();
    KeyboardMovement();
}
 
void MouseAiming ()
{
    // get the mouse inputs
    float y = Input.GetAxis("Mouse X") * turnSpeed;
    rotX += Input.GetAxis("Mouse Y") * turnSpeed;
 
    // clamp the vertical rotation
    rotX = Mathf.Clamp(rotX, minTurnAngle, maxTurnAngle);
 
    // rotate the camera
    transform.eulerAngles = new Vector3(-rotX, transform.eulerAngles.y + y, 0);
}
 
void KeyboardMovement ()
{
    Vector3 dir = new Vector3(0, 0, 0);
 
    dir.x = Input.GetAxis("Horizontal");
    dir.z = Input.GetAxis("Vertical");
 
    transform.Translate(dir * moveSpeed * Time.deltaTime);
}

Example 2: first person camera controller unity

//Fixed the issues with the previous controller
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CameraLook : MonoBehaviour
{
	public float minX = -60f;
	public float maxX = 60f;

	public float sensitivity;
	public Camera cam;

	float rotY = 0f;
	float rotX = 0f;

	void Start()
	{
		Cursor.lockState = CursorLockMode.Locked;
		Cursor.visible = false;
	}

    void Update()
    {
		rotY += Input.GetAxis("Mouse X") * sensitivity;
		rotX += Input.GetAxis("Mouse Y") * sensitivity;

		rotX = Mathf.Clamp(rotX, minX, maxX);

		transform.localEulerAngles = new Vector3(0, rotY, 0);
		cam.transform.localEulerAngles = new Vector3(-rotX, 0, 0);

		if (Input.GetKeyDown(KeyCode.Escape))
		{
        	//Mistake happened here vvvv
			Cursor.lockState = CursorLockMode.None;
			Cursor.visible = true;
		}

		if (Cursor.visible && Input.GetMouseButtonDown(1))
		{
			Cursor.lockState = CursorLockMode.Locked;
			Cursor.visible = false;
		}
	}
}