how to add multiple spaces in html code example

Example 1: leading spaces html

<!--   Add leading white space in front of text  -->

&nbsp;Hello World

<!--    Output:   ' Hello World'    -->

Example 2: tab space in html

<p style="text-indent :5em;" > </p>

Example 3: adding space tab in html

<d style="padding-left:1em;" > </d>