Hello, If you want to obtain a valuable completion certificate then no institute offers certification at free of cost though they may provide course alone at free. The certification cost is very lesser at some institutes though excluding the software cost. You can check out this article to know the websites you can learn the courses online

https://www.careers360.com/articles/want-become-pro-at-adobe-after-effects-use-these-14-courses-learn

You can check out other graphic's design courses from this link https://www.careers360.com/articles/top-10-graphic-design-courses-pursue-online

Best wishes.