Hello! I am trying to find the option for the Menu Item Style in the menu area of the website I'm working on. I've seen it in previous websites I've worked on, but for some reason it's not showing up? Is there a global option I need to activate before I can access that?

I'm trying to turn one of my menu items into a button link. 

I'm attaching a screenshot for your reference of what I'm hoping to locate. 

Thanks in advance! 
Ben