Big Sur (other volumes in Container)
So, I installed Big Sure from a flash, hoping to do a clean install on my iMac. It works fine but I think I did not erase the whole drive because just after install, my HD has "other volumes in container" of 622gb. its like I did not delete the old info off of the computer. Can you advise 1. HOW TO ERASE THAT 622GB WITH DESTROYING MY COMPUTER.
iMac 21.5″ 4K, macOS 11.1