How we can create menu from Appearance > Menu and use as a add-submenu-page for admin menu?

This plugin solved my issue (Seamlessly adds 3 new menu locations to the admin toolbar.)
https://wordpress.org/plugins/admin-toolbar-menus/

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)