JS SDK for CRM and "PageLoad" listener

Hi
Help please with JS SDK, I am not rly using JS besides for widgets. Not a web developer or something

So I am trying create widget for CRM, alrdy have expirience with widgets for desk where use alrdy JS
But for CRM i cant make work this code

ZOHO.embeddedApp.on("PageLoad",function(data)
{
	console.log(data);
	//Custom Bussiness logic goes here
})

/*
 * initializing the widget.
 */
ZOHO.embeddedApp.init();

This is from embeddedApp-js-sdk. I am missing really somethink simple, but cant figur out what.
So when I am checking console log I see error:

"Uncaught ReferenceError: ZOHO is not defined

<anonymous> ...."
I think mb not connect lib to project or someting but it still not work
Please help, I stuck with this task, cant move on
Thank You!