A menu is a list of links on a website that allows its visitors to view its contents. It also helps them navigate the site.
The menu contains links to the subpages of the website and creates its basic structure. The menu often also contains links to posts, categories or other types of site content.
Where the menu is created
You can edit the menu in WordPress administration. Go to Appearance ›Menu . Here you create the menu structure and you can also edit it later.