How to let camera's vertical rotation move the camera up and down?

Question

I have a player in the game, which I can move using the keyboard and rotate only on the horizontal axis using the mouse. That means, I can aim only horizontally and I can not aim it up and down.

I have the Main Camera and another VM Camera from Cinemachine. The current state of the game is like this:

On the horizontal axis, I rotate the player, but on the vertical axis I only want the player's camera/FOV to be moved up and down.

My movement script attached to the player is:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
 
public class PlayerMovement : MonoBehaviour
{
    public CharacterController characterController;
    public float speed = 35f;
    public Animator animator;
 
    // camera and rotation
    public Transform cameraHolder;
    public float mouseSensitivity = 2f;
    public float upLimit = 50;
    public float downLimit = -50;
 
    // gravity
    private float gravity = 9.87f;
    private float verticalSpeed = 0;
 
 
    void Update()
    {
        Move();
        Rotate();
    }
 
 
    public void Rotate()
    {
        float horizontalRotation = Input.GetAxis("Mouse X");
        float verticalRotation = Input.GetAxis("Mouse Y");
 
        transform.Rotate(0, horizontalRotation * mouseSensitivity, 0);
        cameraHolder.Rotate(-verticalRotation * mouseSensitivity, 0, 0);
 
        Vector3 currentRotation = cameraHolder.localEulerAngles;
        if (currentRotation.x > 180) currentRotation.x -= 360;
        currentRotation.x = Mathf.Clamp(currentRotation.x, upLimit, downLimit);
        cameraHolder.localRotation = Quaternion.Euler(currentRotation);
    }
 
    private void Move()
    {
        float horizontalMove = Input.GetAxis("Horizontal");
        float verticalMove = Input.GetAxis("Vertical");
 
        if (characterController.isGrounded) verticalSpeed = 0;
        else verticalSpeed -= gravity * Time.deltaTime;
        Vector3 gravityMove = new Vector3(0, verticalSpeed, 0);
 
        Vector3 move = transform.forward * verticalMove + transform.right * horizontalMove;
        characterController.Move(speed * Time.deltaTime * move + gravityMove * Time.deltaTime);
    }
}

Answer 1

This is the code i use, it works for me, it's super easy to implement, and stops moving the camera when you aren't focusing the game, is the script from one of Brackey's tutorials modified for this purpose:

using UnityEngine;

public class CameraController : MonoBehaviour
{
    public PlayerController player;
    public float sensitivity = 150f;
    public float clampAngle = 85f;
    public bool look = true;

    private float verticalRotation;
    private float horizontalRotation;

    private void Start()
    {
        verticalRotation = transform.localEulerAngles.x;
        horizontalRotation = player.transform.eulerAngles.y;

        // Defines the state of the cursor
        Cursor.lockState = CursorLockMode.Locked;
        Cursor.visible = false;
    }

    private void Update()
    {
        // Looks around if the user is in the window
        if (look)
        {
            Look();
        }
        Debug.DrawRay(transform.position, transform.forward * 2, Color.red);

        // If the player presses ESC while in the game, it unlocks the cursor
        if (look && Input.GetKeyDown(KeyCode.Escape))
        {
            look = false;
            Cursor.lockState = CursorLockMode.None;
            Cursor.visible = true;
        }
        else if (Input.GetMouseButtonDown(0) && !look)
        {
            look = true;
            Cursor.lockState = CursorLockMode.Locked;
            Cursor.visible = false;
        }

    }

    private void Look()
    {
        float _mouseVertical = -Input.GetAxis("Mouse Y");
        float _mouseHorizontal = Input.GetAxis("Mouse X");

        verticalRotation += _mouseVertical * sensitivity * Time.deltaTime;
        horizontalRotation += _mouseHorizontal * sensitivity * Time.deltaTime;

        verticalRotation = Mathf.Clamp(verticalRotation, -clampAngle, clampAngle);

        transform.localRotation = Quaternion.Euler(verticalRotation, 0f, 0f);
        player.transform.rotation = Quaternion.Euler(0f, horizontalRotation, 0f);
    }
}