where to find these files and where to add this code

I’m running WordPress with digitalaccesspass for memberships.

There’s an issue I’m trying to sort, and digitalaccesspass support said to do this:

Please add this to both wp-config.php and /dap/dap-config.php and see if it resolves this issue:

if (!defined(‘SITEROOT’))
define(‘SITEROOT’,’/home/content/20/8843120/html/richardclunandotnet’);

…2 things I’m not sure about:

1. Where in my hosting — what path of files — do I find the two files wp-config.php and /dap/dap-config.php ?

2. And that code I need to add in — I don’t know where to add that in, in the files.

I’m not a techie, so a baby-explanation would be useful. For example, if you give a line of code after which I can add that code, then I can search for that line of code.