Additional Courses completed online

Hello. So I completed a Udemy course online revolving around Data Science. I want to include this on my Commonapp since most of the places I am applying to are for a Major in Data Science. I just wanted to know where I should include this on my application. I was thinking the “Do you wish to provide details of circumstances or qualifications not reflected in the application?” box, but I already talk about an extenuating circumstance. Thank you