Trying to create a drop down menu with arrow on right

I am trying to create a drop down menu NOT A NAVIGATION MENU. Just a single box, with drop down arrow that, when clicked, shows all options. See example here: https://newwpthemes.com/demo/Flamingo/ in the upper right corner (left of “DOWNLOAD”). I found a post on it, but was not able to make it a drop down using that post. When I find drop down plugins, etc. they are usually for a suckerfish type menu, which I am not interested. If you have a plugin or a solution please help. Thank you.