Linux runlevels and retrieve root password

1. runlevel diagram
   

2. The init command switches the run level and
   
   
   enters the following figure
   
   to switch 3-5 successfully
   1), modify the root password. Single-user mode does not require a password to log in.
   The steps are as follows: After starting the virtual machine, press the enter key within 3s to enter the following interface; then press [e] to enter the startup file interface, and then
   
   press [↓] to pull to the bottom; add “LANG=zh_cn.UTF-8” after the peer "init=/bin/sh"; then press [Ctrl+X] to enter "single user mode",
   
   enter [ls], and press Enter; then enter [mount -o remount ,rw / ], press Enter (note the space, refer to the picture ); modify the password input, passwd root; after entering the password twice,
   
   enter [touch /.autorelabel] and press Enter; then enter [exec /sbin/init] and press Enter; restart the system
   and finally everyone can verify it again. I hope everyone has to help