Hello,
Are you talking about the 3d level https://prnt.sc/26k499x ? If you use the drop-down type of the menu it applies for all the menu levels and there is not option to display 2d level as the drop-down and 3d level as the mega menu in horizontal way. Use additional plugins for the mega menu if you want to customize any advanced view for your menu. Built-in menu settings do not have such options, unfortunately.
Regards