The only way to add a 'bookmark' (you refer to it as an 'anchor') to a specific location within an existing web page is to add some script in the html code to the web page. While this works, I think this is more difficult than it needs to be, especially for many of us who are not proficient in using html code.
Please add a tool to your edit functions that will allow a quick and easy method to link a 'bookmark - anchor' to an existing location inside the web page.
By having this tool, the admin person would not have to worry about adding/changing html code.