Looking for logging into the Ubuntu site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Ubuntu site. After that you can login as usual with your login credentials.
https://www.hiroom2.com/2017/05/16/ubuntu-16-04-root%E3%81%A7%E3%83%AD%E3%82%B0%E3%82%A4%E3%83%B3%E3%81%99%E3%82%8B/
https://qiita.com/____easy/items/60d8b5d5ca03a3ce250d
https://kledgeb.blogspot.com/2012/08/ubuntu-18-loginlogout.html
https://login.ubuntu.com/
https://teratail.com/questions/141049
https://teratail.com/questions/156335
https://news.mynavi.jp/article/20180308-ubuntsu_login/
https://linuxfan.info/ubuntu-password-reset
https://www.maketecheasier.com/fix-ubuntu-login-loop/
https://itsfoss.com/how-to-hack-ubuntu-password/
https://askubuntu.com/questions/223501/ubuntu-gets-stuck-in-a-login-loop
https://www.techonthenet.com/linux/sysadmin/ubuntu/login_16_04.php
https://smallbusiness.chron.com/forgot-server-login-password-ubuntu-81716.html