Hi,

at my checkout page I want to add an additional checkbox, where customers will be able to tick the box if they want us to use their email address for marketing purposes (additional and explicit way like this is required by GDPR). 

There is already one checkbox there (required), where customers have to agree with the terms and conditions (screenshot added). Under this one I would like to add another checkbox (not required - stating something like: "I wish to recieve emails about your promotions") + after order is placed I need to recieve information whether customer ticked the box or not, since I need to know if I can use his/hers email for marketing purposes or not. 

How can I do this? Somehow I do not find a way. 

Thank you very much,

Ziga