Are you trying to have a custom area in your WordPress website on the navigation area? That’s called a Custom Post Type. Kori Ashton from https://askkori.com teaches you how to build one using the plugin Custom Post Type UI. It’s a free plugin that easily builds out this custom area for you inside of your dashboard.
Custom Post Type UI Plugin – https://wordpress.org/plugins/custom-post-type-ui/
Kori’s T-Shirt – https://barbacoapparel.com/
Great WordPress Hosting and Support – https://www.liquidweb.com/products/managed-wordpress/