I cant get games because I have to upgrade a iOS 6.0 but I don't know how to do it

This link explains some of the issues with upgrading iPads to newer version of the iOS ...

http://ipad.about.com/od/iPad-FAQ/f/Why-Cant-I-Upgrade-To-iOS-6-0-On-My-iPad.htm

You cannot. The first generation ipad cannot be upgraded past IOS5. You will need new hardware to take advantage of the newer IOS6.

there are two ways to upgrade the iOS version of your iPad
- via connecting the device to iTunes on a computer
- or directly from within the device, but only since iOS 5, it is possible to upgrade the iOS version without the need to connect the iOS device to a computer (over-the-air update)
just go to: settings - general - software update

downgrade to ios 6.

Downgrading from iOS 7 to iOS 6 is for experts only How to

If you have a first gen. iPad you cannot update as it is not compatible with iOS 6

Here Are All The iOS 6 Direct Download Links For Each Supported iDevice...

the first gen. iPad is not compatible with iOS 6
- you need a newer one....
Apple iOS 6 Finally Available for Download Direct Download Link Download Apple iOS 6

- depends on the model of your iPad:
For the iPad first generation (A1219) to update is only possible with connecting the device to iTunes on a computer.
- but this model supports only iOS 5
- NO iOS 6/7/8
---------------------
for all other models:
There are two ways to upgrade the iOS version of your iPhone, iPad, or iPod Touch - via connecting the device to iTunes on a computer
- or directly from within the device, but only since iOS 5, it is possible to upgrade the iOS version without the need to connect the iOS device to a computer (over-the-air update)
just go to: settings - general - software update

depends on the model of your iPad:
For the iPad first generation (A1219) to update is only possible with connecting the device to iTunes on a computer.
- but this model supports only iOS 5 - NO iOS 6/7/8
-------------------------------------------------------------------------------
for all other models:
There are two ways to upgrade the iOS version of your iPhone, iPad, or iPod Touch - via connecting the device to iTunes on a computer
- or directly from within the device, but only snce iOS 5, it is possible to upgrade the iOS version without the need to connect the iOS device to a computer (over-the-air update)
just go to: settings - general - software update

NO
- iOS 6 and higher is not compatible with first gen. iPads!
First gen iPad not getting iOS 6 update Apple confirms

First Generation iPads can use iOS 5
- but iOS 6 / 7 / 8 need an iPad 2 or newer and are not compatibel with first gen. iPhone
-updates can be made in iTunes connected to a computer or under settings - general - software update
Upgrade iOS from within iOS device
(valid for iOS 5 and above)
Since iOS 5, it is possible to upgrade the iOS version without the need to connect the iOS device to a computer (over-the-air update). To upgrade to iOS 6/7/8, simply navigate to Settings > General > Software Update. The screenshot below demonstrates how to do so on an iPad, but this is also valid for the iPhone and iPod Touch.

in iTunes:
How to update to iOS 7