css tag to work only in one html page code example

Example 1: add css file to html

/*
Adding css file into html document
*/

<link rel="stylesheet" type="text/css" href="yourstylesheetname.css">  /* add this line into head tag of the file with change in file name. */

/*
I hope it will help you.
Namaste
*/

Example 2: how to style in html file

<p style="text-align: center; color: pink;">Hello World</p>