Step 4 and Step 5 Facebook setup ( HELP )

A non tech savvy girl needs a help ??

Can anybody explain how to set the following steps for Facebook App setup , please :

4.Click “Website with Faceook Login”, enter your website URL
5.Enter your domain to the App Domain. Domain should be the same domain from URL that you have entered to the “Website with Faceook Login” during the step 4.

Example: when I enter my website xxxxxxxxx.com to the App Domain it shows the following error :
Error
You have specified an App Domain but have not specified a valid integration URL.
bizlifesolutions.com must be derived from one of: Site URL, Mobile Site URL, Canvas URL, Secure Canvas URL, Page Tab URL or Secure Page Tab URL.

Example 2: when I enter my website https://xxxxxxxxx.com/ to the App Domain it show the following error :
Error
App Domains: https://xxxxxxxxx.com/ should not contain protocol information.

WHTA THE H…L I am doing wrong ??

I am not a tech savvy, any help will be appreciated.

Thanks guys,

https://www.ads-software.com/extend/plugins/social-networks-auto-poster-facebook-twitter-g/