Netflix, Streaming Videos & DVDs

which we use to pull in Netflix, Prime, Hulu etc
There is no ROKU subscription; buy the device and go.

Now with a ROKU tv, I believe that means your TV comes with the ROKU capability without an external device. Same with Amazon Firestick

When ever our 'dumb' TV runs out, we will probably get one that has ROKU built in.

Our ROKU cost about $40 I think and you can get one at many places. There are a number of styles. All you need to do is link it to your wireless and you are good to go. Ours just connects to the TV.
Once you get it linked to your wireless, you can add the channels you plan to use. Easy Peasy. ROKU has a number of free channels (like Free Speech TV ); we mostly watch Hulu, Prime/freevee, Netflix, Peacock and Acorn which our subscriptions. We cut our cable 4 years ago.