How to add custom menus and sub menus theme academica

I’m sorry but as you appear to be using a non-WPORG theme, you need to seek support from the theme’s developers – paid or otherwise. We only support themes downloaded from www.ads-software.com here. Try https://www.wpzoom.com/support/

hi, Esmi

If any way I you can help me I will be grateful to you.

Means usually I can use only one menu on top and one on footer but I need to add multiples menu at top.