I came across a free (at least right now) piano class on udemy called Piano Lessons For Absolute Beginners. It seems to have high ratings and might be good for youngsters just to see if they're interested. I'm sharing here because there have been threads about kids and music classes lately.
This looks good and I've heard and come across udemy in various social media platforms. I think it is something anyone keen on learning the piano will love. Overall, anyone can learn any musical instrument here plus there are courses that you pay for as well.