how to add or embed CKEditor in php page, I downloaded and extracted the zip file into root of the directory and also called on my page
After reading the Quick Start Guide
In your HTML page add an element that CKEditor should replace:
Load the classic editor build (here CDN location is used):
Call the ClassicEditor.create() method.
Example
CKEditor 5 - Classic editor
Classic editor
This example is for the specific classic editor. FOr other variants, only CDN will change.