Making Top Level Menus Active

I loaded up your theme and like you I found the top menu item was not clickable.

In this thread:
https://ww.wp.xz.cn/support/topic/menu-still-not-working-on-version-161
the theme author says the parent menu item is not clickable.

In my normal theme the top menu is clickable so if you want this feature maybe you should consider other themes.

I loaded up enigma to look at the menu issue. My normal theme is virtue.

To change the colours would require some knowledge of css. You can use a plugin like this one to enter custom css:
https://ww.wp.xz.cn/plugins/simple-custom-css/

Consider asking at the enigma theme’s support forum:
https://ww.wp.xz.cn/support/theme/enigma