Anyway, Season 3 is apparently not easy to get except buying the discs :/
It's on Showtime. https://www.sho.com/twin-peaks/the-return
Not sure how much that would cost you though. I'm surprised it's not on Netflix since the first two seasons are, but I guess they think it's still selling subscriptions for them.
*Edit* There's a 30 day free trial. Plenty of time to watch it if you want.