Hi Abdul. I'm Greg, an installation specialist, 10 year Windows MVP, and Volunteer Guardian Moderator here to help you.
They are legit IF your school is registered with them. So there is no risk to you if your school refers you, but the school is the one who pays them when it signs up.
See more here:
https://www.reddit.com/r/windows/comments/4ymj2...
To create Windows 10 Installation Media (if necessary on another PC) install the Media Creation Tool and follow the directions in the middle of the Download page here: http://windows.microsoft.com/en-us/windows-10/m.... Uncheck the box for Recommended Settings to choose the exact version and bit rate for the target PC only. This way you get the latest version; you can use the key you get for that version.
Insert media, boot it by powering up PC while pressing the BIOS Boot Menu Key here: https://www.sysnative.com/forums/hardware-tutor...
If the media won't boot you may need to enter BIOS/UEFI Setup (pressing key given in chart in link above) to turn off Fast Boot or Fast Startup first.
Choose the boot device as a UEFI device if offered, skip the Product Key screen and choose your licensed version only if offered. On second screen choose Install Now, then Custom Install, then at the drive selection screen delete all partitions down to Unallocated Space to get it cleanest, click Next to let it create needed partitions and start install - this makes it foolproof.
You will get and keep the best possible install to the exact extent you stick with the steps, tools and methods in this linked tutorial http://answers.microsoft.com/en-us/windows/wiki.... It's a better install than any amount of money could buy and a great learning experience that will make you the master of your PC because you will learn everything that works best and how to apply it with your own hands.
If you have files that aren't backed up you can use the same bootable media to try to rescue your files using this method: http://answers.microsoft.com/en-us/windows/wiki...
I hope this helps. Feel free to ask back any questions and keep me posted. I will keep working with you until it's resolved.
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