Help with forms for a newbie!

Hey folks! Hoping somebody can help - I’m a bit of a newbie here & feel like I’m going a bit mad.

I’ve set up a basic PowerPack Gravity Form, pulling fields from Wordpress. It’s got a checkbox question, but I’m trying to change those basic checkboxes to something a bit more interesting - an example is here:

Those are just buttons with emojis for images, but I can’t figure out how to get those to work within the form!

Any help would be great!!