I’m trying to create a Cyclops race or subraye from Goliaths. I’m trying to add race traits and features but it’s not even allowing me to put anything. There’s the section and drop/ expand menu button but when I press it nothing happens. 

The mobile app doesn't have homebrew, so I am going to assume you are using the website.

The website has an aspect ratio bug where some things don't display properly on narrow screens. Turn the screen sideways and see if that works.