When I start Ubuntu 18.04, login options don't appear; it just logs in automatically.
I want to see a login screen and log in from there. How can I fix this?
Open Settings -> Details -> Users -> Press the unlock icon in the title bar (it looks like a padlock) and authenticate with your user password to make changes -> toggle Automatic Login from ON to OFF. If there are multiple users on your system, then you also need to select the User to disable its automatic login.