WP REST API vs third party REST

NOOB question 🙂
Thanks in advance.

I’m trying to build a widget for showing a list of wordpress posts on an external web site. I intend to use the REST API to dynamically pull the list of posts ( and possibly with excerpts) and display on the external page using jquery. Please advise whats the best API to use as when i search i get various plugins and also see the WP docs for the API ( which i presume is a plugin too).

Am i on the right track or is there a better way to do it?

Thanks