header menu | WordPress.org

New to WP, 1st post.. So I opted to install the Storefront theme because its developed and designed by the WOO team, which is something I plan on using.. I run a small record label and sell a very small amount of items..

My question is really simple, but I cant seem to find, or figure out an answer for this by myself so i figured I need to reach out so i can advance my site..

Lets start with the Header menu (home, cart, checkout, my cart, shop).. I cant find anything, anywhere, that actually calls all these pages.. to be this menu.. I see the pages in my pages section.. But I dont see anything that calls for this menu to be listed as it is.. I’ve also added a page to the pages section, and now that page is showing up in that menu.. which is fine, that’s where I wanted it to show.. what happens if i add a page to pages section that needs to be in a different section??

secondary topic but relative.. that page that i made secondary to the install, lets called it ‘releases”, id like to make that link as a hoverover dropdown menu… how would i go about making that a functional vertical menu?? i do need to make page for each of my menu links..