New to Roku. Only thing I watched on cable were cooking channels and Turner Classic. Was googling a way to watch the good old classics with actors like Cary Grant, Clark Gable, Katherine Hepburn, Spencer Tracy. Read that Roku has a channel called Filmstruck that carries all that but can't find it in the Roku menu.
With the rise of streaming, studios have been cracking down and tightening up licensing deals. It's getting harder and harder find stuff that doesn't require a subscription. There are many quickie movie channels that often have specific movie genres or actors, although the quality may vary, and they may disappear if rights change, or were never there in the first place.
Try HBO Max, they include TCM content. I watch on a TiVo Stream 4K since Roku won't let me. But Roku has Stu's Show, and android tv doesn't....