I restarted the computer and followed the steps to enter safe mode - pressing the F8 key multiple times during startup. Once in safe mode, Windows will start with the most basic settings, and it usually does not ask you to enter a password at this time. Fortunately, this computer was set up with an administrator account without a password, and I logged into the system through this account. Then I was able to go to the control panel and change the password of other accounts through "User Accounts". The whole process was easier than I expected, which was a big relief.