useradd is a low level utility for adding users. On Debian, administrators should usually use adduser(8) instead. the useradd command will update system files and may also create the new user's home directory and copy initial files. manpages.ubuntu.com/manpages/bionic/man8/useradd.8.html
The ‘adduser‘ is much similar to useradd command, because it is just a symbolic link to it. In some other Linux distributions, useradd command may comes with lightly difference version. tecmint.com/add-users-in-linux/
