Backed up Mate ISO image over takes my primary Linux Mint O/S

Have 2 hdd drives not raided or coected to each other .Switch manually.Have Mate 16.04 on a 1 Terra-byte. Linux 17.2 on a 3 Terra-byte . Backed up Mate onto my Linux drive with iso.. Now Linux won't load.Just bios saying Mate saying would you like to try Mate before installing. Legacy was enabled Tried rescue Cd, Live 17.2 cd. Grub 2 cd. None load or work.Not even safe recovery.Linux is on the whole drive .Not partitioned. Gpart doesn't let me set a root folder Linux shows up when i have it in the rom drive. I use the Try Mate before installing.Don't know the command to open my Linux Cd and run and fix from command line. If anyone has an answer?