Discovery
Cable-type channels want to be paid. When you have a paid subscription to a provider service that carries these channels, they receive their pay out of the subscription fees you pay that provider. When you don't have a subscription to such a provider you are not paying for those channels.
Many cable-type channels (like Discovery) only make their programming available for streaming to those paying for them through a provider account as mentioned above, and often do not offer the ability to subscribe to them directly. That provider service doesn't have to be a bloated cable or satellite service however. There are several you can subscribe to and run on a Roku that may carry the channels you are interested in at a lower cost than a cable/satellite subscription. Ones that come to mind to check out for any particular channel would include YouTube TV, Hulu, Sling, Philo, and AT&T NOW -- and a few others.
Savings in cord cutting usually come from picking and choosing which of the lesser offerings you wish to pay for instead of paying for full blown cable or satellite services with scores of channels you never watch.
Discovery PLUS
Discovery+ is one you CAN subscribe to directly, via discoveryplus.com. It includes content from not only DIscover, but from the entire Discovery family of channels, and has additional Discovery+ content that not available elsewhere. To view this subscription on the Roku, install the Discovery+ (not Discovery) app on your Roku, then log in with your Discovery+ credentials.
- Roku Streaming Stick +, 3810X, Ser YH0059427035, wifi - Samsung UN55ES6100
- Roku Streaming Stick, 3600X, Ser 5S56D8240827, wifi - JVC EM37T
- TCL Roku TV 43S425/C107X, Ser X000001R60KV, wifi
