Twig Components / Methods / form_end

form_end(form_view, variables) is a Twig function to render the end tag of a form.

{{ form_end(form) }}

This helper also outputs form_rest() (which is explained later in this article) unless you set render_rest to false:

{# don't render unrendered fields #}
{{ form_end(form, {'render_rest': false}) }}

Source: Forms