In the "Contact Form Element Options" section of your contact form popup type, you can see "Show GDPR Field" option.
Check this option to add a GDPR compliance checkbox inside your Contact form.
You can choose to make it "Required" and add your own "Label" for the checkbox, like: I consent to having Popup Maker collect my details via this form.

Check a detailed article of creating a Contact form popup here: How to use a Contact form?
Check this option to add a GDPR compliance checkbox inside your Contact form.
You can choose to make it "Required" and add your own "Label" for the checkbox, like: I consent to having Popup Maker collect my details via this form.

Check a detailed article of creating a Contact form popup here: How to use a Contact form?
Updated on: 09 / 12 / 2020