Follow Mob Entertainment on Twitter (X) or YouTube. They frequently partner with streamers to give away game keys for free.
If you cannot afford the $19.99 right now, you have safer options than piracy. Poppy Playtime Chapter 3 Free Download
While Chapter 3 isn't free, Chapter 1: A Tight Squeeze is 100% free on Steam. If you haven't played the original, that is a legitimate free download that will give you hours of playtime while you save up. Follow Mob Entertainment on Twitter (X) or YouTube