Hi Tom, sorry for the delay. I go to Design/Appearance –> Theme File Editor –> functions.php and insert the code. This is what I get:
https://apconaero.proceed-it.com/wp-content/uploads/megamenu_codedailure.png
If I insert the code in my code editor into the function.php, the site does not show menu and different things anymore, i. e. not funktion.php is not working.
Thanks, Erika