F5 is typically the refresh key for IE.
F11 toggles between Full Screen and the regular screen – I’ve hit that accidentally and wondered where the menu bars went.
Try Alt+F which brings up the File Menu; I guess Alt+V would bring up the View Menu – which I think is where you’ll find the option to view your address and menu bars.
I don’t browse the web on Windows very often, so I’m just listing the things I’d try. Hopefully, someone with better knowledge will verify this, or will tell you a better way.