How to create multiple checkboxes

I need to add the option for users to be able to select multiple choices from a selection of checkboxes. You can see what I’m trying to do here – https://beta.etoshow.com/register/

It seems that I only have the option to add text fields, selects and single checkboxes to the forms but I need multiple checkbox options. I’ve added the checkboxes to the form but the selected information doesn’t pull through.

Is this possible?

The page I need help with: [log in to see the link]