Hi You can use this below code in your function.php
add_action( 'init', 'register_shortcodes');
function register_shortcodes(){
add_shortcode('go-to-top', 'gtp_function');
}
function gtp_function($atts) {
extract(shortcode_atts(array(
'text' => '<i class="fa fa-arrow-circle-up fa-3"></i>',
'speed'=>500,
'bottom'=>20,
'right'=> 20
), $atts));
?>
<script>
$ = jQuery.noConflict();
(function($){
$.fn.addScrollToTopButton = function(options){
var $t = $(this);
var settings = $.extend({
text : "<a href="#" style="opacity:0.5; font-size:40px" onmouseleave=\"this.style.color="grey"\" onMouseOver=\"this.style.color="#0066CC"\"><i class="fa fa-arrow-circle-up fa-6"></i></a>",
speed: 500,
bottom:20,
right: 20
},options);
return this.each(function(){
$t.html(settings.text);
$t.css({'position':'fixed', 'bottom':settings.bottom , 'right':settings.right});
$t.hide();
$(document).scroll(function(){
if($(document).scrollTop()==0)
{
$t.fadeOut(200);
}
else
{
$t.fadeIn(200);
}
});
$(this).click(function(){
if($(document).scrollTop()!=0)
{
$('html,body').animate({scrollTop:0},settings.speed);
}
});
});
}
}(jQuery));
$(function(){
$('body').append('<div id="gtp"></div>');
$('#gtp').addScrollToTopButton({speed:"<?php echo $speed ?>"});
});
</script>
<?php
}