hello everyone I am new and I have a question I would like to know if it was possible to have a drop-down menu on my site with the theme I use for the moment

website: http://www.rats-trappe-tout.be/index.php

where I would like the drop-down menu these for the category
 
I'm sorry that when we go to this one, it goes with the category desu?

theme used: goodliving_skin

Thank you