Hi erazer,

Thank you for purchasing the theme and our first buyer of KidsWorld theme

You have to add icon html code before top navigation menu link names. For example for home link add like below example code

<i class="fa fa-home"> </i>Home

Icon reference : https://fortawesome.github.io/Font-Awesome/icons/

You can also do quick demo site setup from admin > setup options > import demo data

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