In some instances, the Roku is merely replacing the rented cable box (still paying cable company for access to the subscription channels, though.)
If you want the same channels you had with cable, then you should look at the cable-alternative subscription services such as Hulu, Philo, and YoutubeTV. (These essentially replace the cable provider and provide you access to the channels for a cheaper price.)
In other instances, you can subscribe directly to the channel directly (without using either a cable provider or a cable-alternative provider.) This is channel dependent though. Not all channels offer this route, but more are doing so.
Streaming is a bit different than cable watching. I can tell you I rarely watch the channels that I used to when I had cable/dish services. Everything now is more of an on-demand mentality. Plenty of Channels/apps on Roku that offer free LiveTV and movies. Some channels are "similar" to the cable ones, and some offer the same as cable did. There is a bit of a learning curve with streaming. But basically, if you want almost the same experience as you did with cable but at a little lower cost, then look into the cable-alternative Channels/apps mentioned above. Those will most likely give you the access to the channels you are used to in one place.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
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