Trying to run Windows 10 on my Mac, but having Problems!

Ok, so I have been trying to get Windows 10 running on my 2010 13 Inch MacBook Pro, which I upgraded with a Samsung SSD 860 EVO and 16 GB Of ram. (I also took out the Optical drive for a second SSD to run in Raid 0 - I had to delete that since it didn't work with Windows.) I tried following a Youtube guide by making a copy of Bootcamp and editing the files - and I got everything to work, and the Mac is booting from the USB Flash drive I made - but there are only two options when I hold Alt. The regular Mac os and EFI Boot. When I click EFI Boot, I go through the setup process - until I have to choose my hard drive. I choose the drive that has enough space (400 Gb. The other ones have 0 to 200 MB, so that can't be it.) At first, it said something about NTFS. So I clicked "Format" and that worked - now it's saying the "Selected disk has an MBR partition table. On EFI Systems, Windows can only be installed to GPT Disks." Is there any way to fix this? I have a Windows 10 Disk that I purchased from Microsoft, do I have to use that? Or do I have to run Windows 7??