CineMachine without Timeline?

Forgive me for such noobness. My question is I want to run a Virtual camera based on user input. I have three virtual cameras and I dont know how to do this simple task. And If you know how you could control time line based on User input that will be great.

for changing virtual cameras in code, you can adjust their priorities.

okay here how you can change virtual cameras in code.

using UnityEngine;
using Cinemachine; //do not forget include this

 //assgin your virtual cameras in inspector.
public CinemachineVirtualCamera[] Cameras;

int index =0;

void Update () {
		
		if(Input.GetKeyDown(KeyCode.Space))
		{
                   Cameras[index].Priority =1;
                   index++;
                   index = index%Cameras.Length;
                   Cameras[index].Priority =10;
                 }

every time you press “Space” camera should change.