How to get different homepage layout, based on the URL and customizer

For those who wants to achieve the same, here is the answer:
First we declare a variable with a simple condition to hold our GET request, if the value is not set than we define default value.

$layout = isset( $_GET['home_layout'] ) ? $_GET['home_layout'] : 'standard';

Then simply check the condition and load the template you want.

if ( $layout == 'grid' ) {
    get_template_part( 'template-parts/standard-layout' );
}