Adding Anchors to Sub-Menu Headers


I have created a Sub-Menu for my sub-pages (for articles, project areas etc) but I would like to connect the menu titles to anchors.

e.g. The 'Sub Menu Black' is on 'Off Grid' subpage. I want to click on 'Projects' in the menu and select the Anchor 'Projects' so that when someone clicks on it on that page and all sub-pages, that it will go to the top of the blue 'Projects' section in the website.

Right now when I select the Anchor option in one of the titles, it has nothing to choose from where 'choose anchor' is. And I have alot of anchors I have already generated and used on the main website and all sections.

Help me out?