How exactly will end users open these AMP URLs which are automatically created by ghost?
When I open a post from my website, I am not getting mysite/post1/amp automatically.
Do I need to type the link manually in my mobile browser to be able to read amp version?
AMP pages are automatically used by Google, you don’t need to link to them manually anywhere. When a user searches on Google using a mobile device, Google will serve the AMP version of your page from their own hosted cache.