Basic idea is: you show whole different stuff for mobile users that come from google search. Almost no JS is allowed, only basic styling, critical path should be crystal clear
Google will preload your site when you appear on search, thus your website will open actually instantaneous.
Not confirmed but AMP will not have actual rank boost on carousel stories (whatever that is)
Has it's own JS service worker, html tags, and certain kenpeitai rules
CONCLUSION: No need to do this unless you are a news website. But if you are a news website you gotta do it. For other kind of websites, do it only and only if you have sh.t ton of time in your hands and lookin to waste it.
For wordpress, there is an easy plugin (official) for generating AMP