You can try from recovery options or Advanced startup. You get to that place by holding shift and pressing restart. But might need a bootable Windows flash drive because sometimes even from advanced startup you might not have enough permissions. Plug it in. Go to repair your pc then, I dont remember the exact route, but try to find the terminal (cmd) button. After that change the permissions using the command line. U can sesrch how to take ownership of a fokder or a wholde disk using takeown command and how to change other permissions from CMD.