excerpt length 2 words

Hello,
I am working on the following website: https://66.199.45.174/

I am have problems with the excerpt length, it is only 2 words!

I have tried using the following code:

function custom_excerpt_length( $length ) {
	return 20;
}
add_filter( 'excerpt_length', 'custom_excerpt_length', 999 );

as stated in the following topic: https://www.ads-software.com/support/topic/excerpt-size?replies=4

However, adding this excerpt to my child theme’s functions.php breaks the website altogether. Here is my child theme’s functions.php as of now:

<?php
/*
* Generated By Orbisius Child Theme Creator - your favorite plugin for Child Theme creation :)
* https://www.ads-software.com/plugins/orbisius-child-theme-creator/
*
* Unlike style.css, the functions.php of a child theme does not override its counterpart from the parent.
* Instead, it is loaded in addition to the parent’s functions.php. (Specifically, it is loaded right before the parent theme's functions.php).
* Source: https://codex.www.ads-software.com/Child_Themes#Using_functions.php
*
* Be sure not to define functions, that already exist in the parent theme!
* A common pattern is to prefix function names with the (child) theme name.
* Also if the parent theme supports pluggable functions you can use function_exists( 'put_the_function_name_here' ) checks.
*/

Is there something wrong here? Please advice, thank you.