Hi Avery , you might have noticed the Pop-Ups App on your Dashboard already, but we wanted to jump in to make sure you are aware of the functionality!
To add a pop-up to your website, you need to create a pop-up title and alias first. After that, you will be able to design and customize the light-box the way you desire. You can drag and drop any Element into a pop-up, let it be a subscription element, video or just an image. Take a look at this article for more insight!
Pop-up Lightbox in our Release Notes