How can I disable the auto-select variant option and enable a popup?

[zubairblaze]

Hi guys!

Can anyone guide me to "How to disable shopify autoselect variant option" and get a popup if variant option is not selected?

my them page is "https://siv7g0lud0kzz7nv-61728030919.shopifypreview.com/ " password for preview is "12345". It became nightmare for me. I have done alot of research but failed to find any viable solution.