Hello Guys I need Some help with get my Arduino arduino firmware back

I Installed hoodloader 2 by nico on my Arduino UNO R3 and I want my arduino arduino firmware back please and I tried the flash Arduino by Flip but I can't make the Arduino to atmega16u2 to install arduino firmware I need help please.

Why not just use Arduino IDE to upload the normal bootloader?

how i don't know any thing

Please provide a detailed description of what you did and what happened when you did that.

Did you follow the procedure described here?:

I tried to make my Arduino UNO to HID to use it to control the pc as HID device but I failed....and I did that (I mean convert Arduino to HID) by using NicoHood HoodLoader2.0.5 and I think the hoodloader failed in the installation and now I want to get the firmware back to Factory firmware(I mean the mean firmware of Arduino UNO) but I can't make the Arduino UNO to launch as atmega16u2 by short two pins (near the RX and TX led)...so I short the two pins and nothing happened and I need to launch the Arduino as 16u2 to get the main firmware by using Flip

If you can't get the ATmega16U2 into DFU mode, the alternative is to program it using an ISP programmer. That means you either need a dedicated ISP programmer (e.g., USBasp) or else a spare Arduino board to use as a programmer.

Do you have one of those things?