Mac cross circle
Hi everyone my Imac screen went black and with a white circle in the middle. I turned my mac off. Instructions on internet says to turn on mac then hold the command and R bottoms simultaneously. But I’m afraid this will wipe out all my files. I spend days working on an assignment, I don’t want to lose it. What should I do?
iMac 21.5″ 4K, macOS 10.13