Hello Sunsaan and welcome to AbanteCart forum.
It is not very clear what you set up from the screenshot, but my guess it a category menu what you show.
You can only add categories to the "category" menu.
In original template, there is a menu (home icon) on the left side of the bar. I do not see it on your screenshot.
You can assign specials to that menu. See my screenshot.
If you still need to add a link in the menu that you showed, you will need to edit the category block code or add new block to the right of the category and add link this new block.
Blocks are managed in the layout section.
