Install a Start button
After 20 years on our Windows screens, the Start button (the "orb") has been removed in Windows 8.
Microsoft has given various reasons for this action, and, to support the decision, has reportedly stripped unwanted code from Windows 8 to prevent re-activation.
Despite that, and even before Windows 8 was released, some free and a paid-for utility that create the Start button of old have been released.
Class Shell (http://classicshell.sourceforge.net/index.html) is free (donations welcome) software that is highly customisable. The Start button can show menus in the style of Windows 98 (sort of), XP, Vista and 7. In fact, it is perhaps so customisable as to be a bit confusing. If you install this, look through all the options it presents, and choose the things that best suit your way of working.
In Windows 8, the Windows key normally switches between the tiled tablet screen and the 'normal' Windows desktop. Classic Shell reconfigures this key, and pressing it brings up the Start menu.
There are a few other installs included in the Classic Shell setup. Read all screens carefully as you install Classic Shell so you don't finish up with unwanted items.
This item (http://www.stardock.com/products/start8) is paid for - US$5, but you can try it free for 30 days. It is very much like Classic Shell, but seems a bit easier to configure. And it has the ability to disable the hot corners, a normal but sometimes annoying part of Windows 8.
Another free item at https://www.pokki.com/windows-8-start-menu Of the 3 reviewed here, Pokki is what Microsoft should have provided in recent models. If you try this, test out what is termed 'pinning'.
Pokki's default setting is to boot to the desktop. This can be changed if you want to.