Roku isn't a provider. There's a lot of channels/apps that require a cable TV provider with a package that contains that channel. You can subscribe directly to NFL+ and then sign in using the NFL channel/app on your Roku device, but I don't really know what that gives you. Some of the cable-like streaming services like Fubu, Philo, Sling, etc. have a package that includes the NFL channel. A few months old, but...
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