How to link the toogle icon of Nav Menu to mobile memu template

I added Navmenu and mobile menu template separately.
Navmenu shows the toggle icon automatically and when click the toggle icon, shows the mobile menu area. but mobile menu area is empty. There is no any options to choose the template.
I couldn’t find how to link the template as a mobile menu.
Please guide me how to link the template as a mobile menu of Nav Menu.