To expand on what @Strega2 said, if you already have a subscription to a provider like Disney, MAX, Hulu or other services, no you do not need a separate subscription to view that provider using a Roku device. I have subscriptions to MAX and Prime Video, neither of them through Roku, and I can view their content on any of my Roku devices or my other streaming players as well.
Dan
Roku Community Streaming Expert
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