To create a sticky menu, edit the row element in which the menu is located. Scroll down to the Sticky section in row settings and enable the stickiness.If you are using a transparent header and want to display a header with a background when the user scrolls down, then you can use the show on sticky option. This will display the row having the background only when it becomes sticky and will hide it otherwise.
How to create a sticky menu in Visual Composer?
How to create a sticky menu in Visual Composer?