Menu Item Settings > General
How to change the submenu trigger for individual items
By default, all of your menu items with submenus will inherit the trigger set in your Control Panel settings – Hover, Hover Intent, or Click.
This setting allows you to override that setting on a per-item basis. So if you have 10 items, 9 of which should be hover and 1 of which should be click, you would set the general Control Panel setting to Hover, then use the Trigger Override setting on a specific menu item to turn just that item into a click-trigger.
A common use case would be for a top level search item that opens a dropdown with a search bar. It would make sense for this item to triggered on click, so that the submenu remains open whether the mouse cursor leaves the submenu or not.