First of all, now that your site is back up and running, I suggest that you go to your GoDaddy Cpanel and use the backup utility and create a backup of your site. GoDaddy support personel will help you if you cannot figure it out. But it is easy to do and you should do it often.
To create a Functions.php file for your child theme is easy. Use NOTEPAD on your computer to create a new file. Place the following code in that file. No white space before or after it. Any php code you need to add goes in the middle. Then save it AS functions.php (without capital letters) upload it to the child theme where the style.css file is located. DONT upload it to the Parent theme.
<?php
?>
