can someone help me with a controller joystick thingo

I have an arduino Uno and 1 joystick. i have seen people do this with 2 joysticks on a Leonardo I think. anyway, my arduino doesn't recognise the line

'#include <keyboard.h>'

So it doesn't let me use keyboard commands. I have heard it is intergrated with the leonardo, but if is possible with the uno can somebody please find a soultion.

Two problems:

If you read the documentation of the Keyboard library, you would know it's not compatible with your Uno:

These core libraries allow the 32u4 and SAMD based boards (Leonardo, Esplora, Zero, Due and MKR Family) to appear as a native Mouse and/or Keyboard to a connected computer.

Your filename case is wrong. The filename is Keyboard.h. Even on a filename case-insensitive OS like Windows, the Arduino IDE still requires that you get the filename case right.

Death_Pacito6:
if is possible with the uno can somebody please find a soultion.

If you have an official Uno or a true Uno clone with the ATmega16U2 USB to TTL serial chip then it is possible, but it's a very advanced project:

I think you'd be much better off to just use one of the boards like Leonardo, Micro, or MKR that don't require a lot of extra complexity to use for keyboard emulation.