I have just created a small bash script which will create user without asking for password. It will use random password. At the end it will show you username and password. I have made important 2 lines in bold and highlighted. Please note that It doesnt have any validation on User input or any other validation.
#!/bin/bash
echo -e "Enter Username you want to add:c"
read uname
echo -e "Enter Password age:c"
read page
PSD=`</dev/urandom tr -dc A-Za-z0-9 | head -c8`
useradd $uname
echo -e "$PSDn$PSDn"|passwd $uname
passwd -x $page $uname
echo -e "$uname is created. $PSD is its password and Passwd age is 14 days"