Turn on verbose output for upload. Post the detailed output.
Very carefully check the wiring. Especially the capacitor used to disable auto-reset.
Post of a picture of your wiring that clearly shows each connection.
(None of those are mutually exclusive. Do the ones you can when you can.)
I didn't use a capacitor for reset I connected everything according to the instructions of the official site as i told you and used resistors between the digital pins 13,12 and 11 (that work as MOSI,MISO, SCK)
( https://www.arduino.cc/en/Tutorial/ArduinoISP).. I am trying to post photos but it doesn't show them, so I am attaching links to these photos
Please do this:
Arduino as ISP | Katerina Tsirepa | Flickr
Arduino as ISP | Katerina Tsirepa | Flickr
Arduino as ISP | Katerina Tsirepa | Flickr
The three photos should make a person want a regular ISP programmer. 
kprims:
The three photos should make a person want a regular ISP programmer.https://www.avrfreaks.net/sites/default/files/IMG_0967_0.JPG
Sorry I didn't understand why? is the wiring so wrong?
Sorry I didn't understand why? is the wiring so wrong?
No,No. I was trying to make a small joke.
It only takes one bad connection or component with all of those leads on the breadboards to cause a failure.
Sometimes I can spend a couple of hours trying to make Adruino as ISP work and then the next couple of times it works really well. I don't have this type of problem usually when using a USBasp.
haha ok! I'll try the wiring again and post a photo.. truth is that the resistors or the cables don't always make good contact because when I press them the LED on the Arduino board went on (the orange one with the letter L next to it) and sometimes it turned off... 
Just a quick check. You do have the ON/Power led on, on both Unos?
Well i did the wiring again and now it showed me this! I think I did it!!! it says "Done burning bootloader" :))))
Using Port : COM10
Using Programmer : stk500v1
Overriding Baud Rate : 19200
AVR Part : ATmega328P
Chip Erase delay : 9000 us
PAGEL : PD7
BS2 : PC2
RESET disposition : dedicated
RETRY pulse : SCK
serial program mode : yes
parallel program mode : yes
Timeout : 200
StabDelay : 100
CmdexeDelay : 25
SyncLoops : 32
ByteDelay : 0
PollIndex : 3
PollValue : 0x53
Memory Detail :
Block Poll Page Polled
Memory Type Mode Delay Size Indx Paged Size Size #Pages MinW MaxW ReadBack
----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
eeprom 65 20 4 0 no 1024 4 0 3600 3600 0xff 0xff
flash 65 6 128 0 yes 32768 128 256 4500 4500 0xff 0xff
lfuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
hfuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
efuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
lock 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
calibration 0 0 0 0 no 1 0 0 0 0 0x00 0x00
signature 0 0 0 0 no 3 0 0 0 0 0x00 0x00
Programmer Type : STK500
Description : Atmel STK500 Version 1.x firmware
Hardware Version: 2
Firmware Version: 1.18
Topcard : Unknown
Vtarget : 0.0 V
Varef : 0.0 V
Oscillator : Off
SCK period : 0.1 us
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.02s
avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: erasing chip
avrdude: reading input file "0x3F"
avrdude: writing lock (1 bytes):
Writing | ################################################## | 100% 0.01s
avrdude: 1 bytes of lock written
avrdude: verifying lock memory against 0x3F:
avrdude: load data lock data from input file 0x3F:
avrdude: input file 0x3F contains 1 bytes
avrdude: reading on-chip lock data:
Reading | ################################################## | 100% 0.01s
avrdude: verifying ...
avrdude: 1 bytes of lock verified
avrdude: reading input file "0xFD"
avrdude: writing efuse (1 bytes):
Writing | ################################################## | 100% 0.01s
avrdude: 1 bytes of efuse written
avrdude: verifying efuse memory against 0xFD:
avrdude: load data efuse data from input file 0xFD:
avrdude: input file 0xFD contains 1 bytes
avrdude: reading on-chip efuse data:
Reading | ################################################## | 100% 0.01s
avrdude: verifying ...
avrdude: 1 bytes of efuse verified
avrdude: reading input file "0xDE"
avrdude: writing hfuse (1 bytes):
Writing | ################################################## | 100% 0.02s
avrdude: 1 bytes of hfuse written
avrdude: verifying hfuse memory against 0xDE:
avrdude: load data hfuse data from input file 0xDE:
avrdude: input file 0xDE contains 1 bytes
avrdude: reading on-chip hfuse data:
Reading | ################################################## | 100% 0.01s
avrdude: verifying ...
avrdude: 1 bytes of hfuse verified
avrdude: reading input file "0xFF"
avrdude: writing lfuse (1 bytes):
Writing | ################################################## | 100% 0.01s
avrdude: 1 bytes of lfuse written
avrdude: verifying lfuse memory against 0xFF:
avrdude: load data lfuse data from input file 0xFF:
avrdude: input file 0xFF contains 1 bytes
avrdude: reading on-chip lfuse data:
| ################################################## | 100% 0.01s
avrdude: verifying ...
avrdude: 1 bytes of lfuse verified
avrdude done. Thank you.
Using Port : COM10
Using Programmer : stk500v1
Overriding Baud Rate : 19200
AVR Part : ATmega328P
Chip Erase delay : 9000 us
PAGEL : PD7
BS2 : PC2
RESET disposition : dedicated
RETRY pulse : SCK
serial program mode : yes
parallel program mode : yes
Timeout : 200
StabDelay : 100
CmdexeDelay : 25
SyncLoops : 32
ByteDelay : 0
PollIndex : 3
PollValue : 0x53
Memory Detail :
Block Poll Page Polled
Memory Type Mode Delay Size Indx Paged Size Size #Pages MinW MaxW ReadBack
----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
eeprom 65 20 4 0 no 1024 4 0 3600 3600 0xff 0xff
flash 65 6 128 0 yes 32768 128 256 4500 4500 0xff 0xff
lfuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
hfuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
efuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
lock 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
calibration 0 0 0 0 no 1 0 0 0 0 0x00 0x00
signature 0 0 0 0 no 3 0 0 0 0 0x00 0x00
Programmer Type : STK500
Description : Atmel STK500 Version 1.x firmware
Hardware Version: 2
Firmware Version: 1.18
Topcard : Unknown
Vtarget : 0.0 V
Varef : 0.0 V
Oscillator : Off
SCK period : 0.1 us
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.02s
avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "C:\Users\kat_t\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.6.21/bootloaders/optiboot/optiboot_atmega328.hex"
avrdude: writing flash (32768 bytes):
Writing | ################################################## | 100% 0.00s
avrdude: 32768 bytes of flash written
avrdude: verifying flash memory against C:\Users\kat_t\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.6.21/bootloaders/optiboot/optiboot_atmega328.hex:
avrdude: load data flash data from input file C:\Users\kat_t\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.6.21/bootloaders/optiboot/optiboot_atmega328.hex:
avrdude: input file C:\Users\kat_t\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.6.21/bootloaders/optiboot/optiboot_atmega328.hex contains 32768 bytes
avrdude: reading on-chip flash data:
Reading | ################################################## | 100% 0.00s
avrdude: verifying ...
avrdude: 32768 bytes of flash verified
avrdude: reading input file "0x0F"
avrdude: writing lock (1 bytes):
Writing | ################################################## | 100% 0.02s
avrdude: 1 bytes of lock written
avrdude: verifying lock memory against 0x0F:
avrdude: load data lock data from input file 0x0F:
avrdude: input file 0x0F contains 1 bytes
avrdude: reading on-chip lock data:
Reading | ################################################## | 100% 0.01s
avrdude: verifying ...
avrdude: 1 bytes of lock verified
avrdude done. Thank you.
Good Job!
kprims:
Just a quick check. You do have the ON/Power led on, on both Unos?
Yes now the Led L is on on both UNOs!! I think now it did burn the bootloader 
!!
And yes now y old Arduino is working perfectly !! I uploaded the simple Blink sketch and it works!!!
Thank you everyone for your great help!
OP, try following the steps below:
open you arduino sketch
go to Tools > Processor > and
Choose ATMEGA328P (old bootloader) if by default it was ATMEGA328P or ATMEGA328P if by default it was ATMEGA328P (old bootloader)