As you get accustomed to streaming, you will find that that the different streaming channels will offer the same content. Some of the Channels are free, some are paid subscriptions, and some charge per episode. Normally for free, you will get ads, while the subscription channels and paid per episode channels will be ad-free.
From Roku Search feature, appears that The Saint (Roger Moore), is available for free with ads on Peacock, Tubi, Vudu/Fandango, and Fawesome channels. For ad-free episodes of The Saint, appears you can subscribe to Shout Factory TV on Roku Channel for 2.99/mo, or purchase individuals episodes for 1.99 from Prime Video.
Don't really understand why Shout Factory TV is 2.99/mo on Roku and other streaming devices though, since appears you can watch Shout Factory TV content for free online at https://www.shoutfactorytv.com/ as well as their Shout Factory TV Live Channel 24/7 programming.
If you find you like Tubi, you may want to try the Fawesome Channel.
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