I looked at some of the examples in here and I am still a bit confused. Can someone please provide a simple example of how to bring up another window like a modal popup.
What CSS framework are you using (if any?)
Whatever comes out of the box with cake 3
CakePHP is a PHP framework, not a CSS framework.
CakePHP only does server stuff and not client-side stuff.
I’d highly recommend looking into something like Bulma, Bootstrap or Materialize.
Do you have any examples doing it with Bootstrap?
Just check their docs 
Sorry I am a total newb on this so where do I put the components within the cake framework? so when I click a button in my edit view it should bring up a dialog so do I create some sorta of layout for this? How do i call the layout on the button click?
You should put the Bootstrap files (it’s CSS and Javascript) in the head of your template.
then on the page you want to display it, add the example code I showed you in the BS4 docs.