Contact form - select all checkboxes at once

Design help Custom code
1

Hi,
is it possible to create contact form with a checkbox that let user to select/deselect all other checkboxes?
I need to create a contact form in which user can select all the options with one click.

Thanks for help in advance!
Ula

Here is my site Read-Only: LINK
(how to share your site Read-Only link)

2

Hey, did you ever find a fix for this?