Hi @Mr_Zuriri
here is code and ful tutorial step by step
{% comment %}
Reduce below value if you need the back to the top button to appear higher up on the page.
That value is in pixels.
{% endcomment %}
{% assign vertical_offset_for_trigger = 300 %}
{% comment %}
Vertical offset from bottom of browser for the position of the button.
{% endcomment %}
{% assign position_from_bottom = '7em' %}
Back to the top
{{ '//netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.min.css' | stylesheet_tag }}