Most of us just add a new category called whatever - Resources, FAQs
and then you can add info to the Category page just like a content page.
Depending on what content you want - you could also add a banner block in that area, or use those Main Page Banner Blocks to highlight the Content page and add a link there.
But if you want to add it to the Categories bar (the menu bar is actually the one at the very top of the page, in the header area) you will need to make css adjustments and that's a bit of a hassle and you probably will need to re-do it when there are version upgrades, so I suggest to stay away from code changes as much as possible.