You can try this but make sure you have backup of files that you going make changes just in case you have to go back to original.
There are two changes you need to make in your files to have two custom menus than you will be able manage one for your top bar and one for side bar widget you use that in footer as well if you want.
If you comfortable to add some code in files then open functions.php at very bottom on file before ?> copy and paste this
add_action( 'init', 'register_my_menus' ); function register_my_menus() { register_nav_menus( array( 'menu-1' => __( 'Menu 1' ), 'menu-2' => __( 'Menu 2' ) ) ); }
update the file now if you click on menus in appearance you will see that box has changed and you have Menu 1 and Menu 2 Now we need to put in place of what you have in header file open header.php
look for this <ul id=”NaviBar”>(could be using some other ID for navigation) and take everything out in between and <?php ?> and
copy paste this
<?php wp_nav_menu( array( 'theme_location' => 'menu-1' ) ); ?>
so you should have this
<ul id=”NaviBar”> <?php wp_nav_menu( array( ‘theme_location’ => ‘menu-1’ ) ); ?>
and update the file
Now we need to create the menu Go in Appearance Menus enter name to your menu on box and click on create menu now if you do not see pages box on left click on screen options on top right hand corner tick what ever you want see on the page now you will see boxs.
On left one of them is pages select the pages you want in menu and click add to menu you will see all pages on the right from here you can arrange your pages as you want by dragging To make child page you just drag the page slightly to right under the parent and if want grandchild than drag a page slightly to right of child.
once you done the arranging save menu on the top box Theme locations in Menu 1 select your menu that you just created for top.
You can create 2nd one same way and select that in Menu 2 and then you add that to your sidebar or footer by using custom menu widget give it Title and select Menu 2 from dropdown and save. Let me know if you do not understand any part and let me know if this worked for you.
Let me know if this works