crontab -e lets you edit your crontab and if you add the line
0 21 * * 0 zip -P passw0rd -r /var/backup/secure.zip /home/$USER >/dev/null 2>&1, save and exit your editor, then you have created a new entry that runs the command each Sunday at 9pm.
You can use
crontab -l to display the content of your crontab on stdout without editing it.
The command creates a zip file
/var/backup/secure.zip of the content of your home directory
/home/$USER recursively (
-r) and uses the password option
-P passw0rd to encrypt it with password "passw0rd".
>/dev/null 2>&1 at the end is used to prevent any output of the zip command to stdout and stderr to prevent cron from sending any mails (if successful or in the event of an error).
To unzip the zip file, you will have to enter the password if you use
unzip secure.zip, or use
unzip -P passw0rd secure.zip.