Can you download ios6 or higher on a I generation iPad ios5.1?

Unfortunately you can only update to 5.1.1 for the ipad1

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

on a 1.gen. iPad it is impossible to install iOS6:
this model supports only iOS 5 !
- NO iOS 6/7/8
- the processor is too slow....
For the iPad first generation (A1219) before iOS 5 to update is only possible with connecting the device to iTunes on a computer. Plug it into your computer and open up itunes under devices click on your ipad and then click on check for update.
- but this model supports only iOS 5
- NO iOS 6/7/8 !

no, you cannot.
on a 1.gen. pad it is impossible to install iOS6:
this model supports only iOS 5 !
- NO iOS 6/7/8
- the processor is too slow....
For the iPad first generation (A1219) before iOS 5 to update is only possible with connecting the device to iTunes on a computer. Plug it into your computer and open up itunes under devices click on your ipad and then click on check for update.
- but this model supports only iOS 5

iPad Wi Fi Original 1st Gen 16 32 64 GB Specs iPad Original A1219 MB292LL...

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

you cannot !
on a 1.gen. pad it is impossible to install iOS6:
this model supports only iOS 5 !
- NO iOS 6/7/8
- the processor is too slow....
For the iPad first generation (A1219) before iOS 5 to update is only possible with connecting the device to iTunes on a computer. Plug it into your computer and open up itunes under devices click on your ipad and then click on check for update.
- but this model supports only iOS 5

you cannot!
on a 1.gen. pad it is impossible to install iOS6:
this model supports only iOS 5 !
- NO iOS 6/7/8
- the processor is too slow....
For the iPad first generation (A1219) before iOS 5 to update is only possible with connecting the device to iTunes on a computer. Plug it into your computer and open up itunes under devices click on your ipad and then click on check for update.
- but this model supports only iOS 5

on a 1.gen. pad it is impossible to install iOS6:
this model supports only iOS 5 !
- NO iOS 6/7/8
- the processor is too slow....
For the iPad first generation (A1219) before iOS 5 to update is only possible with connecting the device to iTunes on a computer. Plug it into your computer and open up itunes under devices click on your ipad and then click on check for update.
- but this model supports only iOS 5

on a 1.gen. pad it is impossible to install iOS6:
this model supports only iOS 5 !
- NO iOS 6/7/8
- the processor is too slow....
For the iPad first generation before iOS 5 to update is only possible with connecting the device to iTunes on a computer. Plug it into your computer and open up itunes under devices click on your ipad and then click on check for update.
- but this model supports only iOS 5

For the iPad first generation (A1219) to update is only possible with connecting the device to iTunes on a computer.
- this model supports only iOS 5 - NO iOS 6/7/8