I having an issue no one has been able to fix.

Hi , which operating system do use and what is the year of manufacturing , if you can get hold of 10.10 os on usb and boot

Do you have the option of connecting to another monitor via Thunderbolt or HDMI? That helped me once with a Macbook Pro issue, when the Retina screen went blank but the other monitor showed me what was going on.

Older question, but since I have come across the same laptop recently I can say one or two things for troubleshooting:

Where you installed the OS from onto the drive doesn't matter, as long as it's another genuine Mac (i. e. no OCLP) and as long it's an OS version it supports. Check everymac dot com or the app Mactracker. Here it's everything between 10.9 (Mavericks) and 11 (Big Sur).

I booted such a MacBook off of USB and an SSD with High Sierra (installed from a non Retina model) since no storage was present in the used machine.

As for Macs getting stuck at a certain percentage during booting, I have noticed two possible failures on a 2010 MacBook Pro:

A) The SATA cable between the hard drive/ SSD and the computer was broken. This resulted in very slow boot ups that mostly it didn't finish at all.

The SATA connection on the 2012 Retina model is different than on older ones. So you cannot just change a cable to resolve this, it's likely a tiny component like a resistor, capacitor or MOSFET or so. And perhaps it's not even the issue. Also: If the SATA connection on a 2010 model was the fault, it would still boot up from USB or Firewire, which is not the case here.

B) RAM! MacBooks are very picky about the correct speed in those models where you could still change the modules. So when I put a RAM stick with too high a frequency in the 2010 MBP, it would do exactly that: start booting and giving you hope and then stop at half the way or so, wait a few seconds and then reboot.

If a faulty RAM is the issue here, this is bad luck, unfortunately, since the RAM is soldered on. Technically you can change soldered on RAM, as Dosdude showed in one of his videos, but you need special equipment. So for normal people like me this would mean to change the logic board.

However, there might still be another fault causing this problem and maybe it's just a tiny capacitor or so. Troubleshooting on these computers has become more and more of a hassle.

C) And lastly, since you wrote that you can't get into the recovery option: maybe there's (also) an issue with the built in keyboard and it doesn't register the keys pressed during start-up. This seems to be a common issue with these more modern machines (Retina vs. 2010 models) as soon as they were exposed to moisture.

Connect an external keyboard and see if you can boot into Recovery etc.

However, a faulty keyboard should not keep it from fully booting. (On the other hand, I might be wrong and a missing part completely messes up the Retina's way of working.)