How does Upfront and seo in pages work?

Hi Guys, I was wondering, If I create a new page or edit a page that upfront creates I see inside the wordpress editor pure lorem ipsum text, but when I go to my page it has the text I entered in upfront...

My question is how does this work with seo, do I need to add the text also inside the wordpress editor? Also when I share an upfront page in facebook what is the text it will grab?

Thanks