While installing the openssh-server package, I encountered this error. If you have come across the same problem follow the given steps and you may be all okay in less than a minute. First type this command sudo apt edit-sources in the linux command line. Enter your password if it prompts you. Now, it will prompt you to select an editor. Choose the Nano Text Editor by typing and entering "1" or it will directly open the editor window. Add the "s" at the exact location to replace "http" from "https" and switching to a secure server. Now run the following command, sudo apt-get update This will fix everything. You can follow me on Kali Linux Forums .
On Linux you have to prefix the command with "sudo" keyword to run it with root privileges. It is similar to getting Administrator rights in Windows. The “root” user on UNIX platforms has full system access, like the “Administrator” user on Windows. Your Windows file system is located at /mnt/c in the Bash shell environment. Here are some basic commands of Linux that are similar to Windows. Bash indicates the Linux command and DOS is it's Windows analoge. Change Directory: cd in Bash, cd or chdir in DOS List Contents of Directory: ls in Bash, dir in DOS Move or Rename a File: mv in Bash, move and rename in DOS Copy a File: cp in Bash, copy in DOS Delete a File: rm in Bash, del or erase in DOS Create a Directory: mkdir in Bash, mkdir in DOS ...