Hello,

Can anybody help me to understand: How to create "Trends on Facebook" and how does it works on it?
Look forward to your suggestions.

As above said, you need to know, what metrics you are looking for.
However, below are the few links, which may help you:

Have a glance:
https://addons.opera.com/en/extensions/details/seo-analysis-with-seoptimer/
https://addons.opera.com/en/extensions/details/seoquake-extension/
https://addons.opera.com/en/extensions/details/webrank-seo/
https://addons.opera.com/en/extensions/details/rds-bar/
https://addons.opera.com/en/extensions/details/strike-out-nofollow-links/
https://addons.opera.com/en/extensions/details/ip-address-and-domain-information/