I see a decent number of newbies turn up around the community asking for ideas for something to build. I think text-mode games are underappreciated for this purpose. You can start hacking on one without any external libraries but they can also become incredibly complicated. I offer some general and Haskell-specific ideas for someone starting out:
http://jackkelly.name/blog/archives/2022/05/28/text-mode_games_as_first_haskell_projects/