Button HTML help

How do I change this code so that it emails instead of opens web address?

[at_btn text=" MAKE A BOOKING ENQUIRY " url=“https://www.blah.com/” type=“link” style=“secondary1” size=“medium” corners=“rounded” light=“off” transparent=“off” icon_align=“left” icon_class=“td-star”]

Not sure if I understand what you want. You can make an email link. That will open up the users email client (if they have one).