Both Windows 10 and 11 can show you who's signed into your computer in a few different locations. If you know who's logged in, that can be useful for security and to log out users if needed.
Video tutorial:
How to See All Signed in Users in Windows 10 & 11 - Start Menu
Press the Start button and look towards the bottom.
Any signed-in users will be listed there.
Right-click on any user name to change account settings, lock or sign out any users.
How to See All Signed in Users in Windows 10 & 11 - Task Manager
Press the Windows Key + X, and click on Task Manager.
Click on the Users tab.
Any signed-in users will be listed there.
Right-click on any user name to disconnect that user. You can also right-click and click on Manage user accounts for more.
How to See All Signed in Users in Windows 10 & 11 - Command Prompt