Following is a list of important Storefront topics, that you might want to have a look at.
{% page-ref page="add-custom-controller.md" %}
{% page-ref page="customize-templates.md" %}
{% page-ref page="add-custom-javascript.md" %}
{% page-ref page="reacting-to-javascript-events.md" %}
{% page-ref page="add-cookie-to-manager.md" %}
{% page-ref page="use-csrf-protection.md" %}